Difference between revisions of "Group 18 - Product Name Here"

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[[File:IMAG0446.jpg|thumb|200x100px|'''''Figure 25:'''''  ''Oil pump location'']]
 
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Revision as of 09:33, 5 December 2011

Figure A: A GM 2.2L in-line 4-cylinder engine

Contents

Gate 1: Project Planning

Project Management: Request for Proposal

Work Proposal

Overview

Groups 18 and 7 will be working on a term project of disassembling and reassembling a General Motors 2.2L 4-cylinder engine. After meeting with members of Group 7, we agreed to disassemble the engine from top to bottom. During the dissection process, we will place each part in a labeled zip-lock bag with documentations on how it was removed. We believe that the project will take up to two months to disassemble, reassemble, and analyze all the components of the engine

Group 18 decided to record and take pictures of the dissection process as we move along in order to make for an easier reassembly process. With the help of several tools, screwdriver, wrench, and pliers, we should be able to take apart each and every component of the engine. However, since none of our group member has prior knowledge on how to disassemble an engine, it will be an obstacle on which part we can remove first and what part to remove after without damaging the engine as a whole.

Capabilites/Shortcomings
Group Member Capabilities Shortcomings
Yong Chyi Lim Have general knowledge on engines; passionate about engines; strong leadership skills Never worked with an engine before
Shinn Li Experienced with AutoCad; very alert on what's happening; strong organizational skills No prior knowledge in engines; quiet; procrastinates
Jianzhou Qi Able to digest new information quickly; meticulous Poor organizational skills; weak in the English field
Yie Sing Teh Fast learner; Mechanical skills; Organized lack of motivation
Cheng Siah Chua Good communication skills; willing to learn; experience with AutoCAD; can get work done as soon as possible when told to Procrastinates; limited knowledge in programming

Management Proposal

Meeting

Group 18 has come to a consensus that we will hold a minimum of one meeting per week. The meetings will either be held on Mondays, Wednesdays, or Fridays at 5:00PM, right outside of Lockwood Cybrary. Each one of these meetings will last for a duration of at least three hours. If we happen to fall short on our intended schedule for each phase of the project, additional meetings will be held on either Mondays, Wednesdays, or Fridays as previously mentioned. During the meeting, the Project Manager will give the group an agenda for each member to carry out for that specific meeting. Group members will be allowed to leave early with a valid explanation.

Point of Contact

Group 18 has decided to nominate Yong Chyi Lim as the group leader and with this given role, he will also become the main point of contact. Listed below are the ways he can be reached:

Phone Number 614-787-5308
Primary Email Address yongchyi@buffalo.edu
Alternate Email Address yclim90@gmail.com
Individual Roles
Group Member Title Description
Yong Chyi Lim Project Manager Enforces the duties of each group member; makes sure everyone is in par with the schedule
Shinn Li Technical Writing Expert Proofreads everyone's report to ensure that there are no grammatical errors; main writer for Wiki submissions
Jianzhou Qi Dissection Manager Records what happens in the dissection lab and keeps a record on each day's process
Yie Sing Teh Technical Expert In charge of using computer programs (AutoCAD/Pro Engineering) to reconstruct each component of the engine
Cheng Siah Chua Communication Liason Keeps in touch with Group 7 to record what happened during each dissection lab
Conflict Resolution

Any conflict within Group 18 will be brought to the Project Manager to come up with a just decision. If members are unsatisfied with the Project Manager's decision, the conflict will be presented to either instructor of the course and any decision made by the instructor will be final.

Timeline Chart

A table illustrating Group 18's project schedule and deadlines
Figure B: The above shows a table illustrating Group 18's project schedule and deadlines.

Product Archaeology: Preparation and Initial Assessment

Development Profile

Work on the GM 2.2L in-line 4-cylinder engine was first done in 1982. It was revised and reworked multiple times over the years of its existence which ended in 1999. The biggest factor surrounding the permanency of this engine was the globalization that occurred throughout the globe. The North American Free Trade Agreements allowed different parts of an engine or an engine as a whole to be made and sold around the world, thus, allowing the automotive manufacturer to maximize its efficiency and profit and, at the same time, maintain its competitive edge in the marketplace.

The engine was designed to be fitted into multiple platforms, ranging from mid-size family sedans to small pick-up trucks, which are targeted at clienteles worldwide, including the United States, Canada, Mexico, Europe, South Africa, China and Australia. The GM In-Line Four engine was designed and built for consumer to operate their vehicle under any conditions, provided regular maintenance is done. Hence, during its lifetime, over three million units were produced and sold.

Usage Profile

The role of the GM 2.2L in-line 4-cylinder engine is as the main power source in multiple types of GM vehicles. The engine should be able to translate the gasoline, fuel to the engine, into a force that powers the vehicle such that it could convey the people from point A to point B. This engine is power to vehicles that will be used both professionally and domestically. For example, cars like the Pontiac Sunfire (1990-1991) are family sedans while the Chevrolet S-10 (1982-1999) is a small pick-up trucks mainly used for small businesses. The complexity of the role of this engine is numerous. Its main role is to supply force to move the vehicle while its many sub-roles are to power the generator for electricity in the car, to power the air-conditioning compressors and to power water pump in the car’s cooling system.

Energy Profile

The engine typically functions by converting chemical energy, in the form of petroleum, into rotational energy. First petroleum from the fuel tank is sent to all four cylinders in the engine with the assistance of the fuel pump and fuel injectors. Once sufficient amounts of petroleum is in the cylinder, a combustion in each of the four cylinders, although two at a time, is set off with electrical spark converting the chemical into heat energy via spark plugs that is present at the top of each cylinder. Because of the fuel explosion that occurs, a pressure is created which incurs a linear motion of the pistons. This linear motion of pistons direct results in the rotational torque of the crankshaft via crank-pins which rotates a flywheel with the assistance of a connecting rod. This completes one full conversion process in which majority of the engine’s chemical energy is directed into the camshaft. Some of the energy, however, is used to power the vehicle’s water pump from cooling system, the vehicle’s alternator as well as the vehicle’s air-conditioning compressor.

Complexity Profile

We’ll have to make a few assumptions before we proceed with complexity profile. First, we must define the terms component. A component is defined as a device that is one of the individual parts of which a composite entity is made up; especially a part that can be separated from or attached to a system. Moving on, we define complexity as a group of components working together to achieve a task. Elimination of any component will result in failure to complete such task. Generalization will also be made until further dissecting work can take place.

How many components are used?

There are approximately 1,000 to 2,000 components in an engine. It varies from small components like nuts and bolts to one single component like crankshaft. An estimated of 200 to 300 parts are moving when the engine is working.

The breakdown of the components are as following:

Fasteners The fasteners are mainly consists of nuts and bolts. An estimation of 30 types of nuts and bolts there are in the GM engine. The sizes of nuts and bolts are different and are used in most of the fastening in an engine.

Seals and Rings Seals and rings are mainly used in the engine to close and maintain the oil, water and fuel to ensure there is no contamination or pressure leak. Components like Piston rings that found the in the pistons are used to safeguard the piston from pressure leak and prevent energy loss.

Electrical components The electrical components are important for multiple task and one of the main task is to provide electrical spark to ignite the air/fuel mixture in combustion chamber. The electrical components are mainly consist of spark plugs, spark plugs wires and dynamo that power by the engine itself.

Main accommodating components The main accommodating components are used as a base structure for all the engine components to be installed. They by far consist the least quantity of components in an engine. These parts include engine block, engine head, engine cover and oil sump.

Internal engine components For the internal engine components, we include the following parts in it; crankshafts, pistons, pistons rod, oil pump, timing gear, timing chain, bearings,rocker arms, valves, springs, and push rods. Each of the components has its own functionality and but cannot perform its task alone.

Exhaust and fuel delivery component

The exhaust components are mainly perform its task of deplete out the exhaust gas from the engine. It is consist of exhaust head pipe, exhaust gasket, and some nuts and bolt to tie it down. The fuel delivery components are consist of fuel injectors, fuel pump, throttle body, oil filter and are mainly responsible for delivery fuel into the engine.

How complex are these individual parts?

If the engine is dissected and breakdown into each individual component, each component are actually made with simple design and most of the parts has only one function. However, some parts such as crankshaft requires detailed tweaking so that it wont upset the balance of the crankshaft.

Interactive complexity

The complexity of the engine is highly complicated because there are many parts that involved during the working of an engine. However, most of these parts contain just one function in the engine. For example, the crankshaft is responsible to turn kinetic energy from the piston rods into rotational energy. All in all, the engine are a device that turns chemical energy into kinetic energy for the vehicle.

Material Profile

Materials that are clearly visible

  • Engine block
  • Engine cover
  • Pulleys
  • Exhaust manifold
  • Plastics and rubbers
  • Nuts and bolts

Non-visible materials

  • Cylinder head
  • Cylinder block
  • Valves
  • Pistons
  • Piston rings
  • Springs
  • Crankshaft
  • Exhaust manifold gasket

User Interaction Profile

How does the user interface with the products?

Because the engine was meant to be install in commercially available vehicle, we will make an assumptions that user will interact with the engine only when the user is operating the vehicle. Generally, the user is not able to see the engine due to the engine location in a vehicle. The user interface with the engine by observing the rev count provided by tachometer in the driver seat. Besides that, a fuel gauge is also located in the driver’s seat for the user to observe the fuel available in a vehicle. To operate the engine, the driver will first have to use an ignition key to start off the engine. Moving on, user are able to control the fuel supply to the engine with a throttle pedal located below the right foot of the user. To kill off the engine, user will just simply have to turn off the ignition key. All these interfaces can be carry out provided that the engine has regular maintenance and fuel.

How intuitive are the interfaces?

Overall, these interfaces are very intuitive because it only requires the user to use his/her right foot to control the fuel throttle and an ignition key to start or turn off the engine. We can also conclude that the engine is easy to use.

Is regular maintenance required?

Yes, regular maintenance is required in order for the engine to operate smoothly. The most basic and frequent maintenance job is refueling to make sure the engine have sufficient fuel supply. Other common maintenance job such as engine oil change, engine oil filter change, water refill, spark plug changes and more are necessary to be done too. However, these maintenance jobs require certain technical skills to be carry out.

Product Alternative

What product alternative exist?

Chrysler Mopar 2.2Litre SOHC engine. (1981-1994)

What are the advantages?

The Mopar engine uses Single Overhead Cam (SOHC) design compared to the Overhead Valve(OHV) design in the GM engine, thus it provides better valve timing as the engine hits higher rpm. With better valve timing, the air mixture of fuel and air can be improved greatly and this improves the overall efficiency of engine. And because the structure of SOHC is different from OHV, SOHC engine can be equipped with more valves than OHV engine. This particular Mopar engine has 12 valves compared to 8 valves of the GM OHV engine.

What are the disadvantages?

Because of the fundamental design of SOHC, SOHC engines are typically more complex than OHV engine therefore it requires more parts to create it. Furthermore, some of the engine power will be lost to rotate the camshaft in SOHC engine. Finally the cost of building a SOHC is higher than OHV engine because it requires more components.

Performance comparison

The GM L4 engine produces 120 horsepower at 5000 rpm and 140 ft-lb of torque at 3600 rpm. On the other hand, the Chrysler Mopar engine of 1986 specification produces 97 horsepower at 5200 rpm and 122 ft-lb of torque at 3200 rpm.

Cost comparison

Both GM and Chrysler engine has stopped production and therefore they are only available in used market. A refurbished GM L4 engine cost around 1400$ USD in today’s market and the Mopar engine cost around 1500$. The price differences are not much since both engine is produced in United States.

Gate 2: Product Dissection

Project Management: Preliminary Project Review

Work Plan

The dissection work plan has been carried out successfully by Group 18 and Group 7. However, during the process, we faced several problems.

The first problem that we encountered was sorting and managing the nuts and bolts that hold the components of the engine together. Because an engine contains many bolts and nuts with different sizes, we have to categorize them carefully to avoid any confusion when we have to reassemble the engine.

To solve this problem, Group 18 and Group 7 have agreed to “place each part in a labeled zip-lock bag with documentations on how it was removed” (Gate 1: Overview). To make the process easier, we placed the nuts and bolts that come with the parts into the same zip-lock bag, so that we know which parts the nuts and bolts belong to. For parts that were too big to fit into a zip-lock bag, (i.e., engine head) we placed the nuts and bolts that come with it into a zip-lock bag and labeled the bag “engine head”. With that, we were able to categorize these parts systematically.

Figure 1: Engine Knock Sensor

The second problem that we encountered was that some parts of the engine were unidentifiable by the group. All these parts were sensors and we were not sure what their functions were.

To solve this problem, we identified the codes that were imprinted on the sensors and searched it on the Internet to get the information of these products. For example, given the product on the right, we see that the code “10456209” is imprinted on the component in Figure #1. We searched the code on Google and knew that it was the engine knock sensor. With that, we also identified other parts such as: purge solenoid, oxygen level sensor, and crankshaft position sensor.

The third problem that we faced was figuring out a way to disassemble the piston rod and the piston. After consulting with teaching assistant, Brian Literman, we decided to give up on dissecting it because the tools that were required were not available in Furnas 621. If the required tools were provided, we proposed that to dissect the piston rod from the piston, we’ll heat up the piston rod until it expand and lost its grip on the piston pin. With that, we can take out the piston pin that holds the piston rod and piston together.

In Gate 1’s proposal, Group 18 has “decided to record and take pictures of the dissection process as we move along in order to make for an easier reassembly process.” As a response to that, one of the group members, Jianzhou Qi, was there to record a video of the disassembly process by Group 18. Overall, Group 18 has more than 30 minutes of video footage and more than 60 photos. Group 18 will only use the essential photos to represents the parts and part of the video footage will be used to give a clear view about the solution for the problem we faced while dissecting the engine.

Management Plan

Group 18 has decided to work on the dissection on Wednesdays from 5:00PM to 8:00PM in conjunction with the time slots of Thursdays from 6:30PM to 9:30PM of Group 7. To make sure the dissection process of the engine can be carried out smoothly between the two groups, Adam Lawyer of the Group 7 was present in the workshop to take notes when Group 18 was working on the dissection. In contrast, Yong Chyi Lim of Group 18 was present to keep track of the dissection by Group 7.

A total of three working days were carried out to complete the dissection process. Group 18 worked on October 19th and 24th 2011 and Group 7 worked on October 20th 2011.

Product Archaeology: Product Dissection

Dissection Procedure

Day 1 (Wednesday, 10/19/2011)
Step 1
Figure 2: Exhaust Manifold and Oxygen Sensor
  • Intake manifold
  • Throttle body
  • Fuel injector

Using a 10 mm diameter ratchet socket wrench, untighten the nuts to disassemble the intake manifold from the engine. The throttle body is attached to the intake manifold. To disassemble it, use the same 10 mm diameter ratchet socket wrench to untighten the nuts that hold them together. After that, use the same tool again to untighten the bolts of fuel injector to disassemble it from the engine.

Difficulty: 2 out of 5. Provided with the proper tools, only physical strength is required to untighten the bolts.

Time duration: Less than 5 minutes

Step 2
Figure 3: Water Pump Pulley and Radiator Pipe
  • Oil filter
  • Oil level dipstick

Use your bare hands to take out the oil filter that is attached to the engine block. After that, use your bare hands again to take out the oil level dipstick from the engine.

Difficulty: 1 out of 5. These parts are loosely attached to the engine and can be taken off without any tool.

Time duration: Less than 30 seconds

Step 3
Figure 4: Purge Solenoid
  • Engine coolant pipe
  • Ignition coil

In order to disassemble the engine coolant pipe, use a 15 mm diameter ratchet socket wrench to unscrew the nuts and bolts. After that, use a 13 mm diameter ratchet socket wrench to untighten the nuts and bolts of the ignition coil to disassemble it from the engine.

Difficulty: 2 out of 5. Provided with the proper tools, only physical strength is required to untighten the nuts and bolts.

Time duration: Less than 5 minutes

Step 4
Figure 5: Cylinder Head Cover
  • Exhaust manifold
  • Oxygen sensor

Use a 10 mm diameter ratchet socket wrench to unscrew the hexagon nuts (as shown in Figure 2) to take out the exhaust manifold from the engine. After that, oxygen sensor can be unscrew using hands to turn it anti-clockwise.

Difficulty: 2 out of 5. Provided with the proper tools, only physical strength is required to untighten the nuts and bolts.

Time duration: 1 minute

Step 5
Figure 6: Belt Pulley
  • Water pump pulley
  • Radiator pipe

Use a 13 mm diameter wrench to unscrew the nuts of the water pump pulley (as shown in Figure 3) from the engine. After that, use a 14 mm diameter wrench to unscrew the radiator pipe located beside the pulley.

Difficulty: 2 out of 5. Provided with the proper tools, only physical strength is required to untighten the nuts and bolts.

Time duration: Less than 2 minutes

Step 6
Figure 7: Rocker Arm & Push Rod
  • Purge solenoid

To remove the purge solenoid, use a 15 mm diameter socket wrench to unscrew the nuts and bolts (as shown in Figure 4.

Difficulty: 2 out of 5. Provided with the proper tools, only physical strength is required to untighten the nuts and bolts.

Time duration: Less than 1 minute

Step 7
Figure 8: Mounting Racket
  • Cylinder head cover

Use a 10 mm diameter wrench to unscrew all eight bolts of the engine cover to take it out from the engine (as shown in Figure 5.

Difficulty: 2 out of 5. Provided with the proper tools, only physical strength is required to untighten the nuts and bolts.

Time duration: Less than 1 minute

Step 8
Figure 9: Mounting Plate
  • Belt pulley

Use a 15 mm diameter ratchet socket wrench to untighten the 3 bolts attached to it. After that, use a 17 mm diameter ratchet to untighten the bolts that is located at the center of the belt pulley (as shown in Figure 6).

Difficulty: 2 out of 5. Provided with the proper tools, only physical strength is required to untighten the nuts and bolts.

Time duration: Less than 1 minute

Step 9
Figure 10: Cylinder Head
  • Rocker arm
  • Push rod

Use a 10 mm diameter ratchet socket wrench to untighten the bolts of the rocket arms as shown above. After that, retrieve the push rod located just below the rocker arms (as shown in Figure 7).

Difficulty: 2 out of 5. Provided with the proper tools, only physical strength is required to untighten the nuts and bolts. The push rod can be retrieve by using bare hands.

Time duration: Less than 2 minutes

Step 10

  • Mounting racket
  • Mounting plate

To remove the mounting racket, use a 15 mm diameter socket wrench to untighten the four nuts that hold the mounting racket to the engine (as shown in Figure 8). After that, use a 8 mm diameter wrench and screwdriver to untighten the nuts of the mounting plate to take off the mounting plate (as shown in Figure 9).

Difficulty: 2 out of 5. Provided with the proper tools, only physical strength is required to untighten the nuts and bolts.

Time duration: Less than 5 minutes

Step 11

  • Cylinder head

Use a 14 mm diameter ratchet socket wrench to untighten the bolt with orange color top to take out the engine head block from the engine (as shown in Figure 10.

Difficulty: 2 out of 5. Provided with the proper tools, only physical strength is required to untighten the bolts.

Time duration: Less than 5 minutes

Day 2 Thursday 10/20/2011

(Disclaimer*: Step 12 to Step 18 of the dissection process of the engine was carried out by Group 7 and observed by Yong Chyi Lim of Group 18. Group 18 did not carry out the dissection work as listed below.)

Step 12

  • Cam sprocket cover

Use a 5/16 inch diameter socket wrench and 10 mm diameter socket wrench to untighten the screw to loosen the nuts. However, do not remove the cover. More of this will be covered in the troubleshooting section below.

Difficulty: 2 out of 5. Provided with the proper tools, only physical strength is required to untighten the nuts and bolts.

Time duration: Less than 2 minutes

Step 13

  • Oil sump

Use a 10 mm diameter socket wrench to untighten the bolts of the oil sump to take it out from the engine.

Difficulty: 2 out of 5. Provided with the proper tools, only physical strength is required to untighten the nuts and bolts.

Time duration: Less than 2 minutes

Step 14

  • Crankshaft holder

Use a 16 mm diameter socket wrench to untighten the bolts of the crankshaft holder to take out the holder. There are four holders that hold the crankshaft and each holder are tightened with 2 bolts. After that, use a hammer to tap out the holder from the crankshaft.

Difficulty: 2 out of 5. Provided with the proper tools, only physical strength is required to untighten the nuts and bolts.

Time duration: Less than 2 minutes

Step 15

  • Engine oil pump

To remove the engine oil pump from the engine, use a 10 mm diameter and 16 mm diameter socket wrench to untighten the nuts and bolts on it.

Difficulty: 2 out of 5. Provided with the proper tools, only physical strength is required to untighten the nuts and bolts.

Time duration: Less than 2 minutes

Step 16

  • Pistons
  • Piston rods
  • Piston holder

Use a 13 mm diameter socket wrench to untighten the nuts of piston holder. After that, knock the piston holder lightly with a hammer to take out the holder. Piston rods and pistons can then be taken out together by pushing the piston rod out from the crankshaft.

Difficulty: 2 out of 5. Provided with the proper tools, only physical strength is required to untighten the nuts and bolts.

Time duration: Less than 5 minutes

Step 17

  • Belt tensioner
  • Pusher

Use a 13 mm diameter socket wrench to untighten the bolts of the belt tensioner and take it apart from the engine. After that, use a plier to clamp the pusher and take it out from the engine cylinder block.

Difficulty: 2 out of 5. Provided with the proper tools, only physical strength is required to untighten the nuts and bolts. The pusher can be taken out easily because there’s not nuts or bolts to tighten it.

Time duration: Less than 3 minutes

Step 18

  • Engine knock sensor
  • Crankshaft position sensor

Use a 7/8 inch diameter wrench to unscrew the engine knock sensor from the engine cylinder block. For the crankshaft position sensor, it can be taken off using bare hands.

Difficulty: 2 out of 5. Provided with the proper tools, only physical strength is required to unscrew the engine knock sensor

Time duration: Less than 3 minutes

Troubleshooting
Figure 11: Unknown Part
Figure 12: Crankshaft Cover
  • The first problem that we encountered while working on the dissection process is to figure a way out to remove the crankshaft from the engine. The problem first appeared while Group 7 was working on the engine. Group 7 was having difficulties to remove the crankshaft because of the single part that was attached to the crankshaft. (The part is shown in Figure 11.) The part was covered by the camshaft cover and attached to the crankshaft, camshaft chain as shown Figure 12. With that, Group 7 was unable to proceed with the dissection process even after consultation with the TA, Sid Mukherjee. This situation was observed by Yong Chyi Lim and he brought the problem to Yie Sing Teh, the technical expert of the Group 18. Teh was able to take out the crankshaft together with the camshaft, camshaft sprocket and also the sprocket chain. The dissection process was done using a hammer and a pin and the details are as shown in this video: (http://youtu.be/OcPuJ_Z-AtU) However, the cam sprocket cover was still intact with the crankshaft and we were unable to take it apart.
  • The second problem that we faced while working on the dissection was to remove the valve spring from the engine cylinder head in order to take out the valve spring and valve together. Group 18 first encountered the problem after we dissected the engine on October 19,2011. At first, Group 18 discussed with TA, Brian Literman. Literman suggested that we bring the engine cylinder head to Jarvis Hall because there might have a machine that able to apply enough pressure on the spring and to take the components apart. However, Yie Sing Teh from Group 18 decided that we can take out the valve spring using a 21 mm socket piece and a hammer and the process was carried out successfully with a video shown here: (http://youtu.be/r5bSaHgrx7g) To avoid any confusion, the valve was pulled out from the cylinder block using hands.
  • The last problem that we encountered was to remove the piston ring from the pistons. The problem first appeared while Group 7 was in the middle of the dissection process. Group 7 decided to deal with it later on because they had to continue with their dissection process. Yong Chyi Lim of Group 18 took note of it and presented the problem to Yie Sing Teh, the technical expert of Group 18. To solve the problem. Teh used a plier to clamp the ring out from piston. Here is a video that was recorded to show a clear view of how it was done: (http://youtu.be/3zpBlIgbZGM) . All the piston rings were removed successfully as shown in the video.

Subsystems

Group 18 has categorized the subsystems of an engine into 9 categories as listed below.

  1. Engine management
  2. Engine housing
  3. Engine power source
  4. Engine exhaust/intake management
  5. Engine exhaustion
  6. Engine lubrication
  7. Engine air intake
  8. Engine ignition
  9. Engine cooling

The function of each subsystem is described in the tables below with a clear analysis of the components in each subsystem. All these subsystems are being held together physically with bolts and nuts.

Economic factors plays an important part for the subsystems to be implemented together physically. Since the creation of the first internal combustion engine, engines have been produced using metals and the most conventional way to combined these different metal parts is using physical connection. (e.g. nuts and bolts) Since this engine that group 18 working on is meant to be used in commercial vehicle, cost plays an important part on the manufacturing of the engine and engine manufactures tend to choose the most conventional and most reliable to built the engine to ensure that the cost of the engine is low.

Figure 13: The above shows a diagram with different colors representing the different subsystems along with arrows showing how each subsystem is connected.
Connection of Subsystems

To give a clear view of subsystems, a drawing of the subsystems are shown in Figure 13.

All the subsystems are physically connected to the engine housing subsystem with the exception of engine cooling and engine management subsystem, the drawing shows the position of how each subsystems are located. Any alteration to the position of the subsystems will result in failure of the engine to function. For example, engine air intake subsystem cannot be adjacent with engine exhaustion subsystem.

The engine cooling and engine management subsystems are located in the engine housing subsystem. However, each component has its own position in the engine for the subsystems to fully function. (e.g., Engine knock sensor is located next to the piston and piston rod parts of the cylinder block so that it can function properly.

Details of Subsystems
Engine Management

In this subsystem the purge solenoid is physically connected to the fuel injector. The oxygen sensor is physically attached to the exhaust system. The crankshaft position sensor is mounted inside on the left side of the engine block. The engine knock sensor is physically connected to one of the port in the engine block. The economic factor influences this subsystem because all the components in this subsystem is to manage the efficiency of the engine. With higher efficiency, it can cut down the cost of maintaining the engine.

Component Image Component Name Tools Used Description
Solenoid.jpg Purge Solenoid 16 mm Socket Wrench It is a computer-controlled valve that prevents unused fuel vapors from escaping into the atmosphere while the engine is off. The vapors are stored in the charcoal canister system in the solenoid and are recycled into the combustion chamber when the engine is started.
Oxygen.JPG Oxygen Sensor 16 mm Cresent Wrench Detects the air-fuel mixture of by measuring the amount of oxygen in the exhaust gas.
Crankshaft Position Sensor.jpg Crankshaft Position Sensor Bare Hands Monitors the position or rotational speed of the crankshaft and controls the ignition system timing.
Engine Knock Sensor.jpg Engine Knock Sensor 7/8 inch Diameter Wrench Detects engine knock which occurs within a specific frequency and sends a voltage to the CDI. The CDI will then use the knock sensor to control the ignition timing.
Engine Housing

The engine cover, engine head, engine block, belt tensioner, engine mounting racket and engine mouting plate are all physically connected to engine head by nuts and bolts. Mainly global factor influences this subsystem. This method of generating power existed for a long time and it has been a reliable source of power.

Component Image Component Name Tools Used Description
ECover.jpg Engine Cover 10 mm Diameter Socket Ranch An aluminium cover that covers the engine head.
Ehead.jpg Engine Head 16 mm Diameter Socket wrench Placed above the cylinders forming the combustion chamber and houses the valves, spark plugs and fuel injector.
Eblock.jpg Engine Block 16 mm Diameter Socket wrench Houses the pistons and crankcase. It also has coolant, intake, and exhaust passages and ports.
Btensioner.JPG Belt Tensioner 16 mm Diameter Socket wrench Increases belt tension to avoid slipping.
Emr.jpg Engine Mounting Racket 14 mm Diameter Socket Wrench Secures all pulleys in place.
Ehmp.jpg Engine Head Mounting Plate 8 mm Diameter socket wrench Covers the coolant passage.
Engine Power Source

In this particular subsystem, the piston is physically bolted to the crankshaft. The piston rings are physically snapped on to the pistons. The cranshaft is physically attached to the crankshaft holder and the crankshaft holder is connected with nuts and bolts to the crankcase, and the belt pulley is physically bolted to one end of the crankshaft. Global factor influences this subsystem. This method of generating power existed for a long time and it has been a reliable source of power.

Component Image Component Name Tools Used Description
Pistonrings.jpg Piston Rings Plier There are three piston rings and two compression rings which function as a compression sealing for the piston. Another ring is the oil control ring, which controls the supply of oil to lubricate the piston skirt.
Crankshaft4.jpg Crankshaft Bare Hands Translate the reciprocating motion from the pistons into rotational motion.
Crankshaftholder.jpg Crankshaft Holder 16 mm Socket Wrench Holds the crankshaft in place in the crankcase
Bpulley.jpg Belt Pulley 15 mm & 17 mm Socket Wrench Connected to one end of the crankshaft. It is a belt and pulley system that provides power the electric generator and cooling system.
Engine Exhaust/Intake Management

These parts must be equipped together in order for the subsystems to function properly. Any single component being removed will result in failure of the engine to function . The camshaft, camshaft sprocket, lifter, pushrod, rocker arm, valve and valve spring are physically connected to each other using either nuts or bolts or both of them together. Economic factor plays an important part for the implement of OHV intake/exhaust system in this engine. OHV system is a more conventional system and compared to other system, such as double overhead cam (DOHC), it is cheaper because it require less moving components and therefore cost can be reduced on material and R&D.

Component Image Component Name Tools Used Description
CShaft.jpg Camshaft Bare Hands This is a very crucial part of the engine. It is a "timer" for the valves (when to open and close).
Sprocket.jpg Camshaft Sprocket Rubber Mallet and chisel Acts as a physical connection towards the crankshaft through a steel chain
Lifterss.JPG Lifter Bare Hands Transfers the signal (energy) from the camshaft to the rocker arm
Pushrods.jpg Push Rods Bare Hands Transfers the energy from the lifter to the rocker arm
Rockerss.jpg Rocker Arms 10 mm Socket Wrench Manipulates the valve (closing and opening)
Vspring.jpg Valve Spring Hammer & 21 mm Socket Wrench Manipulates the valve (closing and opening)
Valve.jpg Valve Bare Hands Manipulates the valve (closing and opening)
Engine Exhaustion

The exhaust subsystem is connected to the engine block physically. They're connected because after every exhaust stroke from the piston, there is exhaust gas that needs to be exhausted and the role of the exhaust manifold is to provide as little backpressure as possible for an efficient engine and direct the exhausted gas into the atmosphere safely. The connections are made with 4 16 mm nuts. In this subsystem, environmental factor plays a huge role. The other objective of an exhaust system is to neutralize any harmful emmissions from the engine before it hits the atmosphere.

Component Image Component Name Tools Used Description
IMAG0290.jpg Exhaust Manifold 16 mm Socket Wrench Expels exhausted gas from the engine safely to the atmosphere.
Engine Lubrication

The oil lubrication system is connected to the main engine block physically. They are connected with nuts and bolts with the exception of oil filter (fitted). In this subsystem, the economical factor is the dominant factor. The engine lubricant system is used to prolong all engine components that is moving inside the engine block. (e.g., The piston wall, piston rings, crankshaft. etc. with the low friction lubrication system, the maintainence cost can be brought down. Performance wise, this is not the best option available.)

Component Image Component Name Tools Used Description
IMAG0289.jpg Oil Dipstick Bare Hands Monitors the engine lubricant level
IMAG0288.jpg Oil Filter Bare Hands Filters dirty lubricant and expels clean lubricant
Oilpumper.jpg Oil Pump 10 mm & 16 mm Socket Wrench Pumps lubricant to all corners of the engine to maintain constant temperature and to decreases friction in the engine
Reservoir.jpg Oil Sump 10 mm Socket Wrench Acts as a reservoir to store excessive lubricant and the oil pump pumps the lubricant through the entire engine interior
Engine Air Intake

The air intake subsystem is composed of the intake manifold and the throttle body, and these two components are physically connected. This system is influenced by the economic factor in a way that the amount of air that flows into the engine can determine how efficient the car is.

Component Image Component Name Tools Used Description
IMAG0314.jpg Intake Manifold 10 mm Socket Wrench Evenly distributes air to each of the cylinders
IMAG0315.jpg Throttle Body 10 mm Socket Wrench Controls the amount of air flowing into the engine
Engine Ignition

The engine ignition subsystem is composed of fuel injector, CDI ignition coil, and spark plugs. The fuel injector admits fuel into the combustion chamber, which the CDI ignition coil then sends a signal to the spark plug that creates an electric spark. This then leads the engine through the combustion process. This subsystem is influenced by the economic factor in a way that it determines the fuel efficiency of the car.

Component Image Component Name Tools Used Description
IMAG0336.jpg Spark Plug Bare Hands Creates electric spark to ignite compressed fuel
IMAG0317.jpg CDI Ignition Coil 13 mm Socket Wrench Provides electricity to spark plug
IMAG0316.jpg Fuel Injector 10 mm Socket Wrench Injects fuel into combustion chamber
Engine Cooling

The engine cooling subsystem is composed of a water pump and coolant tube. The coolant tube and water pump works in unison to keep the car radiator cool. This subsystem is influenced by the societal factor in a way that it addresses the safety issue.

Component Image Component Name Tools Used Description
IMAG0286.jpg Coolant Tube 15 mm Socket Wrench Allows coolant to flow through engine to prevent overheating
IMAG0292.jpg Water Pump 13 mm Socket Wrench Circulates water whenever engine is running

Gate 3: Product Analysis

Project Management: Coordination Review

Cause for Corrective Action

The members of Group 18 have been working together for six week and everything is going well except the materials that Group 18 submits into wiki page sometimes do not meet the requirement of the course. Group 18 always submits the work material into Wiki page at the last minute as it usually only gets done one night before the submission due date. As a result, we do not have enough time to double check the gate submission materials and end up missing a huge part of work that is required by the course. Group 18 took note of this when we got our results of the Gate 2 submission, where we scored only 14 out of 50 in the product dissection analysis.

The reason behind this is that 4 out of 5 of our group members are taking Junior level courses, and they each have assignments and group projects from other courses to juggle concurrently. Therefore, they did not have enough time to make sure that everything that was submitted to the Wiki page of Group 18 meets the demand by the course. To solve this problem, Group 18 decided to start on the next gate right after the previous gate. For example, we will start working on Gate 4 right after the submission of Gate 3. Besides that, we have assigned one of the group members to double check the work to make sure that we did not miss any part of the required work.

Product Archaelogy: Product Evaluation

Component Summary

Component Image Component Name Component Code Material Manufacturing Process Function
Solenoid.jpg Purge Solenoid #DELPHI1997278 Plastic/Steel Injection molding for the plastics; die casting for the steel parts This is a computer-controlled valve that prevents unused fuel vapors from escaping into the atmosphere while the engine is off. The vapors are stored in the charcoal canister system in the solenoid and are recycled into the combustion chamber when the engine is started.
Oxygen.JPG Oxygen Sensor Not Available Aluminum/Rubber Drawing for the wire part; extrusion for the casing of sensor; drilling for the holes on the sensor Detects the air-fuel mixture of by measuring the amount of oxygen in the exhaust gas. The date will be send to Engine Control Unit (ECU) for it to regulate the fuel amount needed for the engine.
Crankshaft Position Sensor.jpg Crankshaft Position Sensor Not Available Steel/Plastic Injection molding for the plastic; forging for the screw thread and the round metal part Detects engine knock which occurs within a specific frequency and sends a voltage to the CDI. The CDI will then use the knock sensor to control the ignition timing.
Engine Knock Sensor.jpg Engine Knock Sensor # 10456209 Steel/Plastic Injection molding for the plastic; forging for the screw thread and the round metal part. Detects engine knock which occurs within a specific frequency and sends a voltage to the CDI. The CDI will then use the knock sensor to control the ignition timing.
ECover.jpg Engine Cover #245772527 Aluminum Die casting for the general parts; grinding for a smoother surface and accurate geometry An aluminum cover that covers the engine head.
Ehead.jpg Engine Head #24576144 Aluminum Die casting for the general body; drilling and milling for the final geometry and surface Placed above the cylinders forming the combustion chamber and houses the valves, spark plugs and fuel injector.
Eblock.jpg Engine Block #2033-A3D Steel Die casting Houses the pistons and crankcase. It also has coolant, intake, and exhaust passages and ports.
Btensioner.JPG Belt Tensioner #24574843 Steel/Plastic Injection molding for the plastic wheel; die casting for the metal part Increases belt tension to prevent belt loosening its grip on the sprocket.
Emr.jpg Engine Mounting Racket #24575332 Steel Die casting for the whole body; drilling for the holes on the part Secures all pulleys in place.
Ehmp.jpg Engine Head Mounting Plate #24576136 Aluminum Die casting for the whole body; drilling for the holes in the body Covers the coolant passage to prevent leakage.
Pistonrings.jpg Piston Rings Not Available Steel Forging There are three piston rings and two compression rings which function as a compression sealing for the piston. Another ring is the oil control ring, which controls the supply of oil to lubricate the piston skirt.
Pist.jpg Piston Not Available Iron Forging Compresses the air-fuel mixture before combustion occur, transfers explosion energy of air-fuel mixture to linear motion energy, and pushes out the exhaust gas to exhaust manifold.
Crankshaft4.jpg Crankshaft #GMD-4618 Steel Die casting for the general body; milling and grinding for the smooth surface finish and accurate geometry Translates the reciprocating motion from the pistons into rotational motion.
Crankshaftholder.jpg Crankshaft Holder Not Available Steel Die casting; drilling for the holes on it Holds the crankshaft in place in the crankcase.
Bpulley.jpg Belt Pulley #10112371 Steel Manufacturing process used; forging for the general body; drilling for the holes in the part Connects to one end of the crankshaft. It is a belt and pulley system that provides power the electric generator and cooling system.
CShaft.jpg Camshaft #101012HB1 Iron Forging This component act as a "timer" for the valves (when to open and close) by pushing the lifter up.
Sprocket.jpg Camshaft Sprocket #10198810 Steel Die casting for the general body; milling and drilling for the holes and smooth gear surface Acts as a physical connection towards the crankshaft through a steel chain.
Lifterss.JPG Lifter Not Available Steel Forging for the general body part; grinding for the smooth surface Transfers the signal (energy) from the camshaft to the rocker arm
Pushrods.jpg Push Rods Not Available Steel Forging Transfers the energy from the lifter to the rocker arm.
Rockerss.jpg Rocker Arms Not Available Steel Die casting for the body; drilling for the holes Manipulates the valve pushing the valve and spring down and being push back up bring spring (closing and opening).
Vspring.jpg Valve Spring Not Available Steel Forging Manipulates the valve (closing and opening).
Valve.jpg Valve Not Available Steel Forging Act as a “gate” to allow air-fuel mixture to enter the combustion chamber and seal the combustion chamber. It also allows the exhaust gas to escape from the combustion chamber to exhaust manifold.
IMAG0290.jpg Exhaust Manifold Not Available Steel Die casting Expels exhausted gas from the engine safely to the exhaust pipe and eventually to the atmosphere.
IMAG0289.jpg Oil Dipstick Not Available Aluminum/Plastic Drawing for the stick; extrusion for the casing Monitors the engine lubricant level.
IMAG0288.jpg Oil Filter Not Available Foam/Magnet/Aluminum Rolling for the “cup”; assembled using welding. Filters dirty lubricant and expels clean lubricant.
Oilpumper.jpg Oil Pump Not Available Steel/Aluminum Die Casting Pumps lubricant to all corners of the engine to maintain constant temperature and to decreases friction in the engine.
Reservoir.jpg Oil Sump Not Available Aluminum/Rubber Die casting Acts as a reservoir to store excessive lubricant and the oil pump pumps the lubricant through the entire engine interior.
IMAG0314.jpg Intake Manifold Not Available Plastic/Rubber/Aluminum Injection molding Evenly distributes air to each of the cylinders.
IMAG0315.jpg Throttle Body #C0967 Rubber/Steel/Plastic Forging; drilling Controls the amount of air flowing into the engine.
IMAG0336.jpg Spark Plug #25320502 Porcelain/Aluminum/Steel Forging; extrusion; grinding Creates electric spark to ignite compressed fuel.
IMAG0317.jpg CDI Ignition Coil Not Available Aluminum/Copper/Rubber Injection molding; drawing Provides electricity to spark plug.
IMAG0316.jpg Fuel Injector Not Available Aluminum/Copper/Rubber Injection molding; extrusion Injects fuel into combustion chamber.
IMAG0286.jpg Coolant Tube Not Available Steel Extrusion Allows coolant to flow through engine to prevent overheating.
IMAG0292.jpg Water Pump #24576031JA Steel/Aluminum/Plastic Die casting; extrusion; drilling Circulates water whenever engine is running.

Product Analysis

Camshaft
  • Component Function:

The camshaft is used to lift the lifters and push rod which will then operate the intake valve and exhaust valve. As the camshaft spins, the lobes located on the camshaft will lift the lifters and push rod which will then open and close the intake and exhaust valves in time with the motion of the piston.

  • Component Form:

The camshaft is primarily two dimensional as it has one long axis and there are eight lobes attached to it. It is about 3 feet long, 3 inches wide and 3 inches high. Each lobe is placed at different angle so that the valves open and close at the appropriate time. This component roughly weighs about 4 pounds. A mixture of alloys is used to produce this component. Economical factor influences the production of this component because a mixture of alloys allows this component to withstand wear and making the lobes harder. This component does not have an aesthetic purpose. The surface finish of this component is smooth to avoid as much friction as possible.

  • Manufacturing Method:

Chill iron casting is used to produce this component. Evidence that shows this is the attachment of the lobes which are permanent to the camshaft. The material choice should have impacted this decision because a chilled alloy is much more resistance to wear and harder. Economical factor influences this decision because the production time required is fast and chilled iron casting is a good choice for high volume production.

  • Component Complexity:

On a scale from 1 to 5, this component has a scale of 4 on complexity. An example for a scale of 1 is a nut and for a scale of 5 is the engine block. A nut is simple enough to produce, however, an engine block requires multiple processes to complete as there are holes and specific shape on it.

Camshaft Sprocket
  • Component Function:

The camshaft sprocket is attached to one end of the camshaft along with the timing belt and crankshaft sprocket. It is responsible for maintaining the timing between the crankshaft and the camshaft.

  • Component Form:

The camshaft sprocket has teeth along the outside which allows it to link into the timing belt. It is primarily two dimensional. It is approximately 8 inches long, 0.5 inch wide and 8 inches high. This component roughly weighs about 2 pounds. It is basically made of aluminum. This component does not have an aesthetic purpose.

  • Manufacturing Method:

Die casting is used to produce this component. The material choice should have impacted this decision because aluminum is strong, study and function for a long time without wearing down. Economical factor influences this decision because the production time required is fast and die casting is also a good choice for high volume production.

  • Component Complexity:

On a scale from 1 to 5, this component has a scale of 2 on complexity. An example for a scale of 1 is a nut and for a scale of 5 is the engine block. A nut is simple enough to produce, however, an engine block requires multiple processes to complete as there are holes and specific shape on it.

Lifter
  • Component Function:

The lifter follows the lobes on the camshaft and pushes the pushrod to open and close the intake or exhaust valve. The lifter has a roller that provides optimum contact stresses with the lobes.

  • Component Form:

It is primarily two dimensional. It is approximately 0.5 inch long, 0.5 inch wide and 2 inches high. This component roughly weighs about 1 pound. It is basically made of bronze. This component does not have an aesthetic purpose.

  • Manufacturing Method:

Die casting is used to produce this component. The material choice should have impacted this decision because it helps prevent roller fatique. Economical factor influences this decision because the production time required is fast and die casting is also a good choice for high volume production.

  • Component Complexity:

On a scale from 1 to 5, this component has a scale of 2 on complexity. An example for a scale of 1 is a nut and for a scale of 5 is the engine block. A nut is simple enough to produce, however, an engine block requires multiple processes to complete as there are holes and specific shape on it.

Push Rod
  • Component Function:

The pushrod is used to actuate the rocker arms by the camshaft and lifter.

  • Component Form:

It is primarily two dimensional. It is approximately 8 inches long, 0.4 inch wide and 0.3 inches high. This component roughly weighs about 0.8 pounds. It is basically made of composite steel. This component does not have an aesthetic purpose.

  • Manufacturing Method:

A grinding process is used to produce this component. The material choice should have impacted this decision because composite steel have long been the best engineered material for pushrods. Economical factor influences this decision because the production time required is fast and the precision is very good.

  • Component Complexity:

On a scale from 1 to 5, this component has a scale of 2 on complexity. An example for a scale of 1 is a nut and for a scale of 5 is the engine block. A nut is simple enough to produce, however, an engine block requires multiple processes to complete as there are holes and specific shape on it.

Rocker Arm
  • Component Function:

The rocker arm conveys the movement form pushrod, lifter and the lobe on the camshaft to press down on the valve to open it.

  • Component Form:

It is primarily two dimensional. It is approximately 6 inches long, 1.5 inches wide and 8 inches high. This component roughly weighs about 2 pounds. It is basically made of steel. This component does not have an aesthetic purpose.

  • Manufacturing Method:

Die casting is used to produce this component. The material choice should have impacted this decision because steel rocker arms have a longer cycle life with higher ratios. Economical factor influences this decision because the production time required is fast and die casting is also a good choice for high volume production.

  • Component Complexity:

On a scale from 1 to 5, this component has a scale of 3 on complexity. An example for a scale of 1 is a nut and for a scale of 5 is the engine block. A nut is simple enough to produce, however, an engine block requires multiple processes to complete as there are holes and specific shape on it.

Valve
  • Component Function:

The valve opens and closes to allow air in or exhaust out when the rocker arm conveys the movement to it.

  • Component Form:

It is primarily two dimensional. It is approximately 2 inches long, 2 inches wide and 8 inches high. This component roughly weighs about 1 pounds. It is basically made of steel. This component does not have an aesthetic purpose.

  • Manufacturing Method:

Manufacturing a valve requires a few processes such as CNC machining, grinding and surface treatment. The material choice should have impacted this decision because steel has been known as the best material for it. Economical factor influences this decision because the production time required is long and to ensure precision.

  • Component Complexity:

On a scale from 1 to 5, this component has a scale of 2 on complexity. An example for a scale of 1 is a nut and for a scale of 5 is the engine block. A nut is simple enough to produce, however, an engine block requires multiple processes to complete as there are holes and specific shape on it.

Valve Spring
  • Component Function:

The valve spring ensure valve closure when the rocker arm is not conveying the movement from the push rod, lifter and lobes on the cam shaft.

  • Component Form:

It is primarily three dimensional. It is approximately 1.5 inches long, 1.5 inches wide and 2.5 inches high. This component roughly weighs about 1.5 pounds. It is basically made of steel alloys. This component does not have an aesthetic purpose.

  • Manufacturing Method:

Producing a valve spring requires a few processes such as piece hardening, low and high temperature process. The material choice should have impacted this decision because steel alloys have an exceptionally low force tolerances and relaxation that is required for the valve spring. Economical factor influences this decision because this long process helps improve material properties and increased residual compressive stresses.

  • Component Complexity:

On a scale from 1 to 5, this component has a scale of 2 on complexity. An example for a scale of 1 is a nut and for a scale of 5 is the engine block. A nut is simple enough to produce, however, an engine block requires multiple processes to complete as there are holes and specific shape on it.

Engine Cylinder Block
  • Component Function:

An engine cylinder block has multiple functions. The first function is to act as housing for other components like crankshaft, pistons, and piston rods. The other function of the cylinder block is to ensure that the combustion of the air-fuel mixture can be carry out in a safe and closed environment.

  • Component Form:

The general shape of the component is a rectangular block. It is designed with 4 holes aligned to fit pistons and piston rods. At the bottom, the shape is designed to fit with crankshaft. The dimension of the engine is approximately 2ft x 1ft x 2 ft (L x W x H). The approximate weight of it is around 100 lbs. The block is out of die casting with steel. Economic factor influenced with the usage of material as steel is durable therefore doesn’t need frequent maintenance. The product doesn’t have any aesthetic properties.

  • Manufacturing Method:

The engine block is made using die casting methods. Die casting has been the preferred method by car manufacture to create engine block with a few reasons. First, steel can achieve high fluidity with enough energy and able to form any shape. Besides that, this engine is designed for mass production. Die casting is cheaper and preferred method for high volume production because it is cheaper, compare to other method such as investment casting or machining.

  • Component Complexity:

The block is relatively simple it terms of complexity. The main design concern is the cylinder casing which must be as smooth as possible to reduce friction. It is also needed to be precise in geometry to ensure that there is no air leak for the air-fuel mixture to escape from the cylinder block.

Piston Rod/Piston
  • Component Function:

Piston rod is used to join piston with crankshaft. For the piston, its function is to transfer the energy of air-fuel mixture to the crankshaft through piston rod. The piston and piston rod is function inside the cylinder block.

  • Component Form:

The piston is generally in cup-cylinder shape. The top of the piston is smooth and flat to achieve maximum compression of the air-fuel mixture. A piston is weighed around 500 grams. Pistons are made by die forging, they take an alloy ingot and put it in a machine and press it towards the die and later on, subtractive process also take place to remove the excess material. The preferred material for pistons is steel. The component does not have any aesthetics purposes.

  • Manufacturing Method:

Pistons are made by die forging, they take an alloy ingot and put it in a machine and press it towards the die and later on, subtractive process also take place to remove the excess material. Economic factors influenced this decision as piston must be able to endure the high temperature from air-fuel burning and also the force. Therefore, forging method is preferred since the component can be strengthen under this method.

  • Component Complexity:

Pistons and piston rods are relatively simple in terms of shape. However, the geometry of the piston must be precise to be fitted in cylinder block otherwise the leakage of air-fuel mixture would happen.

Fuel Injector

The fuel injector is attached to the cylinder block and has a main purpose in injecting fuel into the combustion chamber. The fuel flows are controlled by the fuel injector. It is 0.455 kilograms and 38 centimeters long. It is made of aluminum, rubber and copper and has no aesthetic purpose at all.

Capacitor Discharge Ignition (CDI)

The capacitor discharge ignition (CDI) is the electronic ignition system used in this engine. The CDI uses capacitor discharge current output to fire the spark plugs. Weighing 1.82 kilograms the CDI consist of a block of 15cm in length, 15cm in width and 10cm tall and a system of wires with a total length of 70cm. It is made of aluminum, copper and rubber. The rubber in the CDI is used for insulating while the use of conductor should increase the efficiency of electricity flows. Similar to the fuel injector, the CDI has no aesthetic purpose.

Spark Plug

The spark plug is an electrical device that is fitted into the cylinder head. Its function is to create electric spark to ignite the compressed fuel. The spark plug has an insulated central electrode which is connected by a heavily insulated wire to an ignition coil or magneto circuit on the outside forming a spark gap inside the cylinder. It weighs 0.05kg and has a M12 size. It is manufactured from porcelain, aluminum and steel. The porcelain is used for insulating and the aluminum is used for ignition. Being positioned inside the cylinder head, the spark plug has no aesthetic purpose.

Throttle Body

Being part of the air intake system, the throttle body controls the amount of air flowing into the engine. Its movements are directly in accordance to the driver accelerator pedal input. The throttle body has a 50mm diameter throttle plate and is made of rubber, steel and plastic. It has no aesthetic purpose.

Intake Manifold

The intake manifold’s primary function is to evenly distribute air to each intake port in the cylinder head. It weighs 2.3kg and is 40cm in length, 30cm in width and 30cm in height. Made of plastic, rubber and aluminum, the intake manifold has no aesthetic purpose. The use of rubber prevents rust to the intake manifold.

Exhaust Manifold

The exhaust manifold collects the exhaust gases from the four cylinders into one pipe and expels them from the engine safely to the atmosphere. It is made of cast iron, weighs 4.5kg and has dimensions 35cm by 12cm by 15cm. It has no aesthetic purpose.

Solid Modeled Assembly

The CAD program that Group 18 used is the Pro/Engineer Wildfire by PTC. The reason we chose this program is because it is available on the lab computers in Furnas 1019. Besides that, Shinn Li and Yong Chyi Lim of Group 18 are taking MAE 377 this semester. Working on this solid models increased their experience in handling the CAD program.

The components that we chose to work on are: Rocker Arm, Push Rod and Lifter. We chose to recreate these components using a CAD program because based on our skills with CAD programs, we were only able to develop simple designs. Therefore, the rocker arm, push rod, and lifter are the simplest components we were able to recreate.

Figures 14 through 16 show the individual components and Figure 17 shows the assembly of the individual components.

Figure 14: CAD View of a Lifter
Figure 15: CAD View of a Push Rod
Figure 16: CAD View of a Rocker Arm
Figure 17: CAD Assembly of Figures 14 through 16

Engineering Analysis

The crankshaft is the most important component in the engine; without it there would be no conversion of chemical energy to mechanical energy. The crankshaft is always spinning and has a radial movement. This may cause the crankshaft to be subjected to various forces such as stress and bending forces. Therefore, the material used must be able to withstand all the forces that might affect this component to function. Other than that, the material should be light too so that the crankshaft can obtain revolution without much loss of energy.

Problem Statement:

  • What should be done to strengthen the crankshaft while the weight of the crankshaft fittingly commensurate so that obtaining a revolution is easy?

Diagram:

Crankshaft4.jpg

Assumption:

  • Gravity is constant at 9.81 m/s²
  • No friction

Equations:

  • Total Force = mass x gravitational acceleration
  • Total Moment = force x distance
  • Normal Stress = force / area

Discussion:

  • The main source of forces applied to the crankshaft is the product of pressure build-up in the combustion chamber acting on the top of the piston. This will, then, produce substantial bending, torsional moments, tensile, compressive and shear stresses on the crankshaft. Another source of force imposed on the crankshaft is piston acceleration. The combined weight of the piston, ring package, wristpin, retainers and the connecting rod are being continuously accelerated from rest to very high velocity and back to rest twice with each crankshaft revolution. Many of the common engine arrangements allow for complete balancing of these forces and moments by having certain angle of crankpin spacing. Steel alloy is typically used because it has the strength and hardness required.

Design Revisions

Figure 18: SOHC Engine Head Block
Figure 19: OHV Engine Head Block

The proposed main design is to replace the Overhead Valve (OHV) design with a Single Over Head Cam (SOHC) design. With this, there are three design changes that will need to be done to make sure that the SOCH design is complete.

The first design alteration is to remove the lifter and pushrod in the engine. Because the camshaft will be powered by a sprocket which is connected to the engine crankshaft with a belt. Therefore, push rods and lifters are not necessary and can be removed.

The second design alteration is to redesign the engine head block and cylinder block. For the engine head block, the position of valve and valve spring will need to be changed to V-shaped form to accommodate a camshaft in between them. Figure 18 and 19 shows an OHV engine head and a SOHC engine head.

Because the position of camshaft has changed, the cylinder block no longer needs to be fitted with the camshaft. Therefore, the cylinder block can be designed without creating a space for the camshaft.

The third design alteration is to add a belt to connect the camshaft sprocket to the crankshaft. An additional pulley might need to be attached to the crankshaft in order to rotate the camshaft sprocket.

The reason Group 18 proposed a SOHC engine is influenced by economic and environmental factors. By using SOHC layout, the camshaft lobes will be directly in contact with the rocker arms, unlike in OHV engine where the camshaft lobes have to transfer its energy to rocker arms through lifters and push rods. Therefore, pushrods and lifters can be eliminated and with less moving parts, the energy loss of the engine can be reduced and thus create a more efficient engine. For environmental concern, a more efficient engine can reduce emission. Besides that, a more efficient engine can also reduce the running cost and thus make it more economical for the user.

Furthermore, the SOHC design has less reciprocating mass than a OHV design, thus the engine can achieve higher revolution per minute (RPM). With higher RPM, the engine can create more horsepower even if the displacement is both the same. With this, a wider range of car model can share the same engine and the car manufacturer can reduce cost in developing more engines. With the cost of develop reduced, the vehicle can be sell at lower price and thus it’s economically beneficial for the user.

Gate 4: Product Explanation

Project Management: Critical Project Review

Cause for Corrective Action

Figure 20: Pistons and Piston rings

For the Gate 4 preparation and submission, Group 18 needed to collaborate with Group 7 for the reassembly work. To meet each group’s best interest, we decided to follow the same procedures we did for the dissection of the engine. Therefore, Adam Lawyer of Group 7 showed up at Group 18’s reassembly work on Wednesday (11/30/11) and observed the reassembly process carried out by Group 18. In return, Yong Chyi Lim of Group 18 showed up on Thursday (12/1/11) and observed the reassembly work by Group 7. The reassembly work was done on 12/1/11 without any unexpected circumstances.

Another challenge that Group 18 faced was the presentation of our work. We needed to decide on who and how many of us would be the voice and representative for Group 18. After discussion within group members, Group 18 nominated Yong Chyi Lim, the leader of Group 18, to represent the whole group and give the presentation alone.

Product Archaeology: Product Explanation

Product Reassembly

Figure 21: Crankshaft

Difficulty scale

The difficulty scale that we are using is based on scale of 1 to 5, where 1 is being easiest and 5 is being the hardest. The detailed scale are as shown below:

Scale Difficulty Description
1 Novice The work can be done without dependency of tools and can be carry out using only hands.
2 Easy The work can be done with required tools being used. Physical strength might be required to get the work done.
3 Average The work can be with required tools and physical strength. However, the work might need more than one person in order to carry out the job.
4 Hard The work might require special tools in order to carry out. To overcome the lack of special tools, creative use of the available tools in the garage is required and may need more than one person to finish the work.
5 Impossible The work is not possible to be done by undergraduate student’s level of engineering skills.

Reassembly Procedure

Day 1 (Wednesday, 11/30/2011)
Figure 22: Piston rod holder cap and Crankshaft holder cap
Figure 23: Camshaft
Figure 24: Oil pump
Figure 25: Oil pump location
Figure 26: Oil filter
Figure 27: Belt tensioner

Step 1

  • Pistons
  • Piston rings

Attach the piston rings into the seal gap of pistons as shown in (Figure 20). After that insert the pistons into the engine cylinder block. (Look for the troubleshooting section for the detailed instruction of how to insert the pistons into the cylinder block.)

Difficulty: 4 out of 5

Tools required: Plier, Hammer, Screwdriver

Time duration: 10 minutes

Step 2

  • Crankshaft
  • Piston rod holder cap
  • Crankshaft holder cap

Insert crankshaft plate at the bottom of the cylinder block (Figure 21). After that, insert the crankshaft to the bottom of the cylinder block. Ensure that the piston is aligned with the crankshaft so that the crankshaft can be fitted in properly. Next, assemble the piston rod holder cap (Figure 22) and tighten the nuts with a 14 mm socket wrench. Finally, attach crankshaft holder and tighten the nuts with a 15mm socket wrench.

Difficulty: 3 out of 5

Tools required: 14 mm socket wrench, 15 mm socket wrench

Time duration: 10 minutes

Step 3

  • Camshaft
  • Camshaft sprocket
  • Camshaft chain

Insert camshaft into the hole at the side of the cylinder block. Next, use a hammer and knock the camshaft sprocket gently to make sure it attach with the camshaft (Figure 23). Subsequently, assemble the chain that connects between camshaft and crankshaft.

Difficulty: 2 out of 5

Tools required: Hammer

Time duration: 5 minutes

Step 4

  • Oil filter
  • Oil pump
  • Oil sump

Position the oil pump as shown in Figures 24 & 25. After that, tighten the nuts of the oil pump with a 10 mm and 16 mm socket wrench. Next, Assemble the oil sump and tighten the nuts that come with it with a 10 mm wrench. Finally, assemble the oil filter to the side of the engine block (Figure 26).

Difficulty: 2 out of 5

Tools required: 10 mm and 16 mm socket wrench

Time duration: 10 minutes

Step 5

  • Water pump
  • Belt tensioner

Assemble the belt tensioner and water pump to the side of the engine block as shown in Figures 27 & 28. Use a 15 mm socket wrench to tighten the center bolt of the belt tensioner and use a 10 mm socket wrench for the water pump

Difficulty: 2 out of 5

Tools required: 10 mm socket wrench, 15 mm socket wrench

Time duration: 5 minutes

Step 6

  • Valve spring
  • Valve

Assemble the valve spring and valve on the engine head block. (For the detailed instructions, refer to the troubleshooting part.)

Difficulty: 4 out of 5

Tools required: 15/16 inch wrench, screwdriver, hammer

Time duration: 10 minutes

Day 2 (Thursday, 12/1/2011)
Figure 29: Lifter
Figure 30: Push rods & rocker arms
Figure 31: Spark plugs
Figure 32: Oxygen sensor & exhaust manifold
Figure 33: Crankshaft position sensor, engine knock sensor, & purge solenoid
Figure 34: Belt pulley
Figure 35: Engine mounting plate
Figure 36: Oil dipstick
Figure 37: CDI ignition coil
Figure 38: Mounting rack & coolant tube
Figure 39: Throttle body & fuel injector
Figure 40: Intake Manifold

Disclaimer*: Step 7 to Step 11 of the reassembly process of the engine was carried out by Group 7 and observed by Yong Chyi Lim of Group 18. Group 18 did not carry out the dissection work as listed below.)

Step 7

  • Lifter
  • Push rod
  • Rocker arms
  • Engine head block
  • Engine head cover

Insert lifters to the side of the engine block (Figure 29). Next, assemble the engine head block on top of the engine cylinder block and tighten the bolts of the engine head block with a 16 mm socket wrench. Subsequently, insert the push rods and rocker arms and tighten the nuts of the rocker arms with a 10 mm socket wrench (Figure 30). Finally, assemble the engine head cover using a 10 mm socket wrench to fasten the nuts.

Difficulty: 2 out of 5

Tools required: 10mm & 16mm socket wrench

Time duration: 10 minutes

Step 8

  • Spark plug
  • Exhaust manifold
  • Oxygen sensor
  • Crankshaft position sensor
  • Engine knock sensor
  • Purge solenoid

Insert spark plug into the side of the engine block as shown in Figure 31. Next, attach the oxygen sensor to the exhaust manifold before insert it to the side port of the engine block. Tighten the 4 nuts with a 13mm wrench (Figure 32). After that, insert the crankshaft position sensor, engine knock sensor, and purge solenoid to the side of the engine block (Figure 33).

Difficulty: 2 out of 5

Tools required: 13 mm socket wrench and 8 mm socket wrench

Time duration: 10 minutes

Step 9

  • Belt pulley
  • Engine mounting plate
  • Oil dip stick

Attach the belt pulley to the side of the engine and tighten the 3 nuts on it with a 15 mm wrench (Figure 34). Assemble the mounting plate to the side of the engine block with a 8 mm socket wrench (Figure 35). After that, attach the oil dip stick to the hole near the exhaust manifold (Figure 36).

Difficulty: 2 out of 5

Tools required: 15 mm & 8 mm socket wrench

Time duration: 5 minutes

Step 10

  • CDI Ignition Coil
  • Mounting rack
  • Coolant tube

Assemble the CDI Ignition coil to the engine mounting plate with 13 mm socket wrench. Connect the tube to the spark plug (Figure 37). After that, attach the mounting rack to the side of the engine followed by coolant tube and fasten the both of it with a 13 mm socket wrench (Figure 38).

Difficulty: 2 out of 5

Tools required: 13 mm socket wrench

Time duration: 10 minutes

Step 11

  • Throttle Body
  • Fuel Injector
  • Intake manifold

Assemble the throttle body and fuel injector to the intake manifold using 10 mm socket wrench (Figure 39). After that, attach the whole assemble to the side of the engine using 10 mm socket wrench (Figure 40).

Difficulty: 2 out of 5

Tools required: 10 mm socket wrench

Time duration: 10 minutes

Troubleshooting
  • The first trouble we faced is to insert the piston into the engine block. Because the circumference of piston rings is larger than the circumference of the cylinder block, the piston rings will block the way of the piston into the engine. This can be solved using a few screw drivers and a hammer and the detailed procedure is in the video (http://youtu.be/6WO9zoiCHjc).
  • The second trouble we faced is the assembly of the valve and valve springs. The valve springs has a relatively high spring constant force and therefore it is hard to compress it and lock it with the valve. To solve this problem, a big wrench and a screwdriver is required and the detailed procedure is shown in the video (http://youtu.be/2GZq5rqPd8U).

Design Revisions

  • The first design revision is to change the overhead valve (OHV) system of the engine to overhead cam (OHC) system. This GM 2.2 4 cylinder engine has an overhead valve (OHV) where the camshaft is installed inside the engine block and valves are operated through lifters, pushrods and rocker arms. OHV design has been used for decades but it is difficult to precisely control the valve timing at high rpm due to higher inertia caused by larger amount of valve train components such as the lifters, pushrods and rocker arms. Thus, redesigning the OHV into an overhead cam (OHC) is a better choice as the camshaft installed in the cylinder head directly operating lifters on the valves. With the camshaft almost directly operating, it is much easier to achieve the perfect timing at high rpm. The advantage of this system is that it will save more fuel, efficient and will definitely be more reliable compared to OHV engine. OHC is much more efficient and reliable because there is less related components and allows for higher engine speeds. Compared to OHV, the OHC reduces the complexity and mass of the engine too.
  • The second design revision is to add a turbocharger to the engine. To complete the design changes, the intake manifold and exhaust manifold would have to be redesign to fit a turbine and the extra pipe-work. Besides that, the engine bay in the vehicle might need to be redesigned to fit in more components. Because turbocharged engines harness its exhaust gas to spin the turbine and compress the intake air/fuel mixture, turbocharged engine have higher power output compared to a Natural Aspirated (NA) engine like this GM engine. Economic and environmental concerns greatly influenced this design revision. For economic concern, a turbocharged engine can be more efficient and thus decrease the fuel consumption of the engine, which helps the user to reduce the running cost of the vehicle. With decreased fuel consumption, the emission of the engine can also be reduced (Environmental).
  • The third design revision is to change the fuel type the engine uses from gasoline fuel to hydrogen fuel. The design revision includes changing the fuel injection system and fuel burning system. This design revision is influenced by societal and environmental factor. For societal factor, people are getting “green conscious” and tend to look for ways to live a lifestyle that has less carbon footprint. With the hydrogen engine, it will appeal to the “green conscious” people since hydrogen engine only emits water as its exhaust waste. Since there is no carbon dioxide emitted from the engine, it can be safely said that the engine is environmental friendly.