Group 24 - GM Inline Four Cylinder Engine
Contents |
Request for Proposal
The first step in reverse engineering process is to take an initial look at the engine and estimate what will be required for this process. For this reason we have put together a work and management proposal, to cover the initial phase, product break-down. We have also created a road-map of where we believe we should be and when for the rest of the project. This plan can be seen in the Gannt chart in the management proposal.
Work Proposal
The dissection of an engine requires tools, space, knowledge and time. The dissection will take place in the lab where the engine is stored, it should contain all the tools necessary to complete our task. As for knowledge, Adam Shellenberger did a significant amount of work on car engines in high school, making him an excellent resource that our group will make use of over the course of this project. He is familiar with most of the parts that go into an engine as well as how it works. Time is the greatest constraint on this project, not only for the dissection. We have found times when at least 3 members of the group can meet and will do dissection during these periods of time.
Capabilities
- Most members of the group have some experience with a CAD package, this should allow our modeling expert to delegate tasks during the modeling in order to speed things up.
- The technical expert has an excellent understanding of car engines, this should make product disassembly and reassembly go quickly and smoothly. Other members of the group are familiar with the tools required and are familiar with basic product tear down procedures. This should prove greatly helpful to the technical expert during dissection.
Challenges
- Only one team member has a working knowledge of internal combustion engines. While this does make him an asset to the group, without him present during the dissection we could run into problems identifying parts or disassembling them.
- We have a large and complex engine with many pieces, keeping everything organized could become a problem during dissection and reassembly. A number of different bolt lengths, threads and head sizes are used, keeping careful track of each variant is very important.
- None of the group members have experience creating or editing a Wiki page, so our Wikipage Designer will have to learn many new things as the needs present themselves.
Plan for Dissection
Regardless of the number of parts, dissection of any product follows the same procedure; remove each piece in the order which they are available. We plan on disconnecting everything that we have access to, and then disconnecting the pieces which are exposed. In this way we will eventually disconnect every part from its neighbors. This is, of course, a simplification of the actual process required to dissect an engine but it conveys the basic concept of how product dissection occurs. Throughout the process we will be labeling and keeping track of parts, regardless of size and shape. Every piece connects to its neighbors in a specific way and the multitude of bolts are not all the same length or threading. A variety of tools will be needed for this endeavor, see below for the list of tools.
Necessary Tools
- Engine Mount - Without a means of elevating the engine and rotating it this project would be nearly impossible. Certain pieces of the engine are secured to the bottom of other pieces, so without access to the bottom of the engine we would never be able to fully dissect the product.
- Socket Wrench - A socket wrench with a set of hex sockets is absolutely essential. Every bolt we have located is a hex bolt, ranging from 8mm to 16mm.
- Crescent wrench - Some locations it may be simpler and easier to use a crescent wrench rather than a socket wrench, having the correct sized crescents available could be invaluable
- Mallet - Some force is required to separate press fit parts such as the bearings on the crankshaft and connecting rods for the pistons/
- Pliers - In some cases parts may want to turn which are supposed to remain stationary, in which case pliers would allow us to prevent or force motion as needed.
Management Proposal
An important step in any project is estimating the amount of time required to complete each step and figuring out how to fit all of that work into the period available for the project. To this end we created this Gantt chart, detailing each of the steps and when that step is to be completed. Another important thing is organization. Our group meets on Monday, Wednesday, and Friday from 4:50-5:00pm to discuss where each member is with his assigned tasks and figure out who will be working on what in the future. We communicate mostly via email, with phone calls and text messages used in the case of time-sensitive questions.
Project Personnel
- Randolf Zingo - Project Manager, Communications Liason
- Main Point of contact between Group 24 and the professor and teaching assistants
- Ensure that all group members know what tasks they must complete
- Ensure that the group stays on track for deadlines
- Kwok Chan - WikiPage Designer
- Learn how to create and edit the WikiPage
- Add content to the Wiki Page throughout the course of the project
- Work with the Lead Researcher to improve the WikiPage based on his research
- Adam Shellenberger - Technical Expert
- Supervise the product dissection
- Supervise the product reassembly
- Responsible for the technical details included in
- Jacob Bober - Media Director, 3D Modeling Expert
- Take pictures and video of the product
- Production of the 3D models of parts
- Aaron Selkridge - Lead Researcher
- Researching topics that no group member has experience in
- Researching past projects to find ways of improving our own
- Collaborate with the Wikipage Designer to incorporate research
Initial Product Assessment
Intended Use
The product we have received is a GM Four cylinder in-line engine. The intended use of this product is, by definition, to use different forms of energy (in this case comes from fuels and oxidizers that undergo combustion to produce very high temperatures and pressures) to produce mechanical work or torque. This engine will produce mechanical work from the energy in the high-pressure high-temperature combustion chambers to spin the wheels, in most cases, on an automobile.
- This product would lie mainly under the field of home or personal use because of its commercial use in automobiles; however, this does not exclude this product from professional use. In fact, this product can be very helpful in professional use, whether in the use of research, company cars, or even to produce mechanical work in any innovative way outside of automotive use, such as using the mechanical work produced or torque to produce electricity or even power generators.
- The four-cylinder engine’s main function is to produce mechanical work for automobiles out of combustion, which produces high pressure and temperatures. The mechanical work, or torque, produced by the engine is used to spin the tires on an automobile. The other functions of this product will all relate back to the necessity of work. Whether linear or rotational work is needed; the engine can provide both. If rotational work is needed to spin the wheels on an automobile, to power a generator to produce heat or electricity, or if torque or mechanical work is needed to operate a large pulley or gear system, the the engine can perform the task.
How It Works
There are four steps for a cylinder engine to work. The cylinder and piston is initially compressed together. Electricity pulls the piston down and creates a vacuum inside the cylinder. Air and fuel are bought into the cylinder. The piston moves up and compresses the fuel air mixture again. The mixture is then ignited and undergoes combustion process. Mixture will quickly expand by pushing the piston down. At the end, mixture exhaust comes out from the cylinder. This reciprocating motion of the piston keeps the crankshaft rotating.
- Electrical energy, Chemical Energy, heat Energy, mechanical energy.
- First, the battery gives electrical energy to start the cylinder engine by pulling the piston down. Air and fuel mixture are forced into the cylinder due to the difference in pressure. Electrical energy is again used to compress the mixture and then ignite it. The ignited mixture undergoes combustion, and a chemical reaction between fuel and air produces gases such as carbon compounds, nitrogen oxide and water vapor. This process greatly increases the pressure inside the cylinder, which forces the piston to move down. Finally, the exhaust valve opens, and the high pressure of cylinder expels the gases.
Functionality
Without some major overhauling, our engine is destined to remain a paperweight. Many of the parts have had sections cut away to allow a view of the inside, rendering them unusable. Among the cut open parts are the oil filter, the main housing, the oil pan and many of the tubes have also been cut open. If we were to replace quite a few parts it would most likely function, but the cost and time required to accomplish this make it hardly a worthwhile task. Therefore, it will remain a large complex paperweight.
Complexity
Our 4-cylinder gas engine falls about halfway between the two extremes. Among engine designs, steam engines are about as simple as they get, so we used that as our lower reference point. For the high end we have the jet engine, which is very complex. Between those two extremes are two-stroke engines, four-stroke engines, diesel engines in order of increasing complexity.
- There are innumerable nuts, bolts and small pieces that make up each component of our product. The outside shell is basically large pieces of steel from molds, held together with bolts and attached in some way to every other piece of the engine. There are pipes running into and out of this shell to provide fluid flow, whether that be air, exhaust, coolant, fuel, or oil. Inside the engine block are 4 pistons (1 per cylinder) with 2 valve assemblies per piston. The valves are opened and closed by the cams on the rotating camshaft. The pistons spin the crankshaft which then goes through a system of gears to provide the desired output. Among the other important parts are the oil pan, oil pump and oil filter, without which the engine would quickly cease to function. Our engine also contains a carburetor to regulate the blending of air gasoline that the cylinders receive. One final important piece of the engine is the spark plug, without which there would be no combustion.
- Engines as a whole are fairly complex, but when broken most of them are quite simple. The majority of parts in an engine are metal from molds, mostly steel with some aluminum. What makes an engine complex is the number of simple parts that it combines and how tight the tolerances are on these parts. Parts in an engine have very tight tolerances in order to prevent the leak of high pressure fluids. If the parts don't fit perfectly it is potentially hazardous as well as messy and inefficient. Although relatively simple in shape, every piece has been extensively tested and modified to optimize performance and efficiency.
Materials
The majority of the engine is made out of only a couple different metals, with the most highly used one being steel. Aluminum is used in our engine for a few different components, but it is not nearly as prevalent as steel. As with most systems that use electricity, the engine contains copper wires. Copper is also used for small pipes in a few locations. A few small components, like caps on pipes and snaps connecting wires are made out plastic, as well as the . Rubber is used in all the hoses on our product and covers for a few other components.Prior to our receiving it most of the oil was removed, but in the oil filter there is still a small amount of oil as well as the expected filter paper.
- Due to the holes cut in our product, more components are visible than would be seen in a functional engine. Steel makes up the majority of what can be seen, the entire outside shell is composed of it as are some of the components inside the engine block itself. Among other things, aluminum is used in the headers. Plastic coats all of the wires and is the material used in the caps on the oil reservoir and a few other things. Rubber and copper tubes provide fluid flow throughout the engine, with rubber forming the ones designed to be disconnected and moved easily. Copper and rubber also form the wires and insulation that connect the spark plugs and a few other components which require electric power. Oil and filter paper can be seen in the cross-section of the oil filter.
- We know that the engine contains spark plugs, so therefore there is a small amount of porcelain. In addition to what we can see, we know there is a lot more steel and aluminum in use. Aluminum camshafts and pistons are used, and the springs on the valve assemblies are made out of steel.
Product Review
If I had to use this product I would be very happy with it. The majority of the developed world's population rely on engines very similar to this every day for transportation. This engine and others very similar to it provide power to personal generators, cars, and most anything which runs on gasoline. Every time I've used a gasoline-fueled engine I have been very happy with it, given that the alternative is performing the same task by muscle alone.
- Engines are not thought of by most as being particularly comfortable. However, very few would say that their engines cause them any amount of discomfort either. Therefore, we can temporarily conclude that engines fall at about a 5 when it comes to comfortability. While during operation they make a fairly large amount of noise, this is offset by the use of sound-deadening materials. As a result, the sound of the engine is barely noticeable when driving. Because driving provides an immensely more convenient and comfortable way of traveling than by walking, this ups the overall comfortability to about a 7 or 8 since there are no real drawbacks.
- The ease of which this product can be used varies somewhat from person to person, but for the most part, is considered quite simple. Starting a properly functioning engine inside a well running automobile consists of inserting and turning the key. There are other small requirements that must be met, such as having the car in park, but for the most part it is as simple as a twist of the hand. For someone with no basic training (and therefore a lack of the knowledge above), getting the engine to start could be a small challenge, but for anyone with a driver's license it is incredibly easy to use and takes virtually no thought.
- An engine requires a few different types of "regular" maintenance. The first type would be something that often, such as filling the tank with gasoline. This is something that anyone who drives is capable of doing. The other type of "regular" maintenance is that which is not required often, but follows a regular cycle, such as once every x number of miles. This includes changing the oil, filters, and hoses. While these are not incredibly complex, the average person does not have the knowledge and experience to know how to do such tasks. Most people take their engines into a shop to have it done for them by trained professionals.
Alternatives
Although the gasoline engine has become the most common, there are many different alternatives, each with their own advantages and disadvantages.
- Steam engines were the pioneer for gas, they used steam to push a pistons forward and backward, thus producing double the power produced by a conventional gas engine which only gets one power stroke. Unfortunately, steam engines were given up for gas engines and not engineered much after that so they lack power and reliability compared to gas engines.
- On the other side of the spectrum, jet engines are some of the most advanced and powerful made to date. Since they are so powerful thought they are rarely used for anything but airplanes and they are very expensive to build maintain and run.
- Electric motors have arguably been gasoline's main competitor from weed-whackers to cars, as they are a clean, efficient motor with instant power and very reliable, but very few are able to match the power output of gas motors. The biggest downside to electric motors is that they need batteries to power them which becomes a chore when powering large machines.
- After those comes diesel motors which have been around about as long as gas motors, yet they have been used mostly for heavy loads, such as 18 wheelers, submarines, and earth moving vehicles. Diesel engines are very powerful, do not require spark plugs, and the fuel is usually more resistant to price fluctuation. However, the engines are louder, have a distinctive smell, and do not work well in cold conditions.
- Another power source is a nuclear reactor. Unfortunately they are not very efficient, produce radioactive waste, cost far to much for commercial use, and are extremely large. Though they are an alternative, it looks very unlikely that nuclear power will become main stream anytime in the near future.
- Finally, the newest technologies have yielded a new style of motor which is hydrogen powered and has the possibility to replace the gas engine. Hydrogen power is clean, efficient, and the only byproduct is water, but the technology is still new and will need years to be engineered and adapted to become a threat to the gas engines. Also, the threat of how reactive hydrogen is becomes a safety risk in the event of accidents.
Preliminary Project Review
Causes for Corrective Action
Our group sat down before even beginning to take the engine apart and decided how we would go about doing this in an organized and efficient manner. We realized that, when it came to an engine, the planning would be more important than the actual disassembly. Our first action was getting into the lab and looking at what we had to work with. Adam, the car expert of the group, outlined the general plan for which we would go about taking the engine apart. We later went back and began taking it apart piece by piece, starting from the outside and working our way in. As we went along we kept notes of the order of which each piece was removed. The pieces were then bagged, and a description of the piece, as well as what tool was used to remove it, was placed on each bag. This plan worked perfectly, as by doing so we essentially already had the disassembly chart (seen below) done. By reversing those steps and following the information on the bags, we will be able to easily reassemble the project when the time comes. In this way we have already overcome many of the future problems we potentially could have come across by staying organized and adhering to the original plan, which called for “removing each piece in the order which they are available” and “labeling and keeping track of part regardless of size and shape."
Product Dissection Plan
This product is not something that is considered easy to take apart. It has many small pieces, and if things are not kept track of and organized when being removed, putting it back together becomes a nightmare. Also, upon reassembly things need to be tightened and attached very specifically in order for the engine to function properly. Because of this most people take their engines in to a shop to be worked on by professionals. While we are by no means professionals, the product does not have to be returned in working condition (since it did not function upon receiving it).
Bolts of various sizes hold most of the pieces of the engine together. This is because bolts are sturdy, yet removable, and can also be adjusted with a few twists of a socket wrench. All three of these are essential, due to the fact that engines must be solidly built, but also must be capable of being dissembled and adjusted when problems occur.
As previously mentioned, the main tool used to dissemble an engine is a socket wrench with various size attachments to account for the different sized bolts. Gloves are also recommended, as many parts must also be removed by hand. Regular wrenches can be used for things in tight spots where a socket wrench will not fit.
The chart below is a guide to taking an engine similar to this one apart. Included are difficulty rankings for each step, ranging from “1” to “3”. Where:
- The part required very little effort to remove, usually involved unscrewing a few bolts or pulling the piece off.
- The part requires some effort to remove, usually hard to reach bolts or parts that require force to remove
- The part is difficult or time-intensive to remove, usually due to tight spaces within the engine making it difficult to remove a part or many long fasteners
| Front view | Back view | Right side view | Left side view | Top view |
|---|---|---|---|---|
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| Step | Difficulty | Procedure | tools | Image |
|---|---|---|---|---|
| 1 | 2 | Disconnected three spark plug wires by hand | hand | |
| 2 | 1 | Removed two bolts connecting the spark plug mounts to the valve cover | hand | |
| 3 | 2 | Used deep sockets to unscrew and remove the 3 spark plugs | deep socket | |
| 4 | 1 | Unscrewed the three bolts holding the distributor, removed the distributor | socket | 
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| 5 | 1 | Unscrewed the five bolts holding the distributor mounting plate, removed the plate | socket | |
| 6 | 1 | Removed the two bolts holding the coolant thermostat | socket | 
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| 7 | 1 | Unscrewed and removed the oil filter | socket | |
| 8 | 2 | Removed the six bolts and one nut holding the intake system on, pulled it off | socket | 
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| 9 | 1 | Removed four nuts holding the exhaust pipes to the header | socket | |
| 10 | 2 | Unscrewed the one bolt holding the dipstick, pulled it out | socket, hand | 
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| 11 | 2 | Unscrewed the two bolts holding the coolant tube, pulled it out | socket, hand | 
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| 12 | 1 | Unscrewed the eight bolts in the valve cover, lifted it off | socket | 
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| 13 | 1 | Unscrewed the eight bolts holding down the eight rockers, lifted off all the rockers | socket | 
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| 14 | 1 | Pulled out the eight pusher rods which connected the rockers to valves | hand | |
| 15 | 3 | Removed ten bolts holding cylinder head, lifted it off the engine block | socket | 
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| 16 | 2 | Peeled the head gasket off the engine block | hand | 
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| 17 | 1 | Removed pin on engine mount, flipped over the engine to gain access to the bottom | hand | |
| 18 | 1 | Unscrewed the twelve bolts the oil pan, lifted it off | socket | |
| 19 | 1 | Unscrewed the one bolt securing the oil pump, removed it | socket | 
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| 20 | 1 | Unscrewed two bolts from the connecting rod caps | socket | |
| 21 | 2 | Pulled off all four connecting rod caps | hand | |
| 22 | 3 | Pushed & tapped the four pistons our of their cylinders | hand, mallet | 
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| 23 | 3 | Removed two bolts each from each of the four journal bearings, used a rubber mallet to knock the housings loose | socket, mallet | 
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| 24 | 2 | Removed crankshaft by hand | hand | 
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Coordination Review
Component Summary
Components
Parts with a complexity of 1 are simple, either having a very simple shape or requiring very few processes to create.
Parts with a complexity of 5 are incredibly complex, requiring many processes to form and a very intricate shape.
| Name | Quantity | Material | Manufacturing Process |
Function | Complexity | Photo |
|---|---|---|---|---|---|---|
| Exhaust Pipe | 1 | Steel | Sand Mold | Divert exhaust gases away from engine into exhaust system | 1 | 
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| Intake | 1 | Plastic Aluminum |
Injection molded plastic die cast metal machined |
Mix fuel and air before it enters the cylinders | 5 | 
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| Head Gasket | 1 | Steel Silicone rubber |
Stamp Paint |
provide a seal between cylinders and headers | 3 | 
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| Dip Stick Tube | 1 | Painted steel | bend tube Weld plate |
store dipstick | 2 | 
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| Dip Stick | 1 | Steel plastic |
Stamped steel molded plastic |
read oil level | 1 | 
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| Oil Filter | 1 | Steel, filter paper | Stamped metal Insert paper |
Remove contaminants from oil | 5 | 
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| Distributor | 1 | Plastic Aluminum |
Molded plastic die cast metal |
Transfer power to spark plugs in specific order | 5 | 
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| Distributor Mount | 1 | Aluminum | Die cast Machined |
hold distributor to engine block | 2 | 
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| Spark Plug Wire | 3 | Rubber Plastic Copper |
Extrude wire encase in plastic & rubber Crimp connectors on ends |
Transport power from distributor to spark plugs | 2 | 
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| Header Cover | 1 | Aluminum | Die cast | Cover header, seals header | 1 | 
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| Distributor Mount Gasket | 1 | Aluminum paint |
Stamp metal Painted |
Prevent heat or electricity travel between block and distributor | 2 | 
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| Coolant Tube | 1 | Steel | Bended tube Welded Plate Machined |
Transfer coolant from radiator to engine | 2 | 
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| Oil Pump | 1 | Aluminum | Sand cast Die cast Machined |
Pump oil throughout the engine | 4 | 
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| Oil Pan | 1 | Steel Paint |
Die cast | Hold oil reserve | 2 | 
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| Piston Bearing | 4 | Aluminum | Die cast Machined |
Hold connecting rod to crankshaft | 4 | 
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| Piston Head | 4 | Aluminum | Die cast Machined |
Compress air and gas mixture in cylinder, transfer power to crankshaft | 5 | 
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| Piston Connecting Rod | 4 | Steel | Sand cast Machined |
Connect piston to crankshaft | 3 |
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| Crank Shaft Bearing | 5 | Aluminum | Die cast Machined |
Hold crankshaft in place | 4 | 
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| Engine Block | 1 | Steel | Sand cast Machined |
The housing for internal combustion | 5 | 
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| Crank Shaft | 1 | Steel | Sand cast Machined |
Transfer energy from piston to output shaft | 5 | 
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| Rocker Assembly | 8 | Steel | Die cast Machined |
Open and close valves via springs and the camshaft | 4 | 
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| Push Rod | 8 | Steel | Machined | Transfer energy from camshaft to rocker assemblies | 1 | 
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| Coolant Valve | 1 | Steel | Sand cast Machined |
Regulate flow of coolant | 4 | 
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| Spark Plug | 3 | Porcelain Steel |
Machined Molded |
Ignite air fuel mixture | 3 | 
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| Metal Bracket | 1 | Steel Paint |
Molded Painted |
Hold coolant tube in place | 1 | 
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| Header | 1 | Aluminum Steel |
Cast Machined |
Seal cylinders and allow air fuel mixture into them | 5 | 
|
Exhaust Pipe - Sand molded steel is used for high wear resistance. No external force is applied to this component. The shape and manufacturing process would be the same regardless of the chosen metal. This component requires a particular shape, in order to connect other parts. Sand mold is used for low cost. It is a functional component.
Intake - This component is made by plastic. So the temperature of fuel and air mixture is not easily affect by the engine. No external force is applied to this component. This component requires a particular shape, so the plastic are molded to the desired shape. The manufacturing process would be different if it is not made by plastic. It is a functional component.
Head Gasket - Steel is used for strength. A partial of force generated by combustion will transfer to this component. This component requires a particular shape, it is stamped and cut out of a sheet. The shape and manufacturing process would be the same regardless the chosen metal. It is a functional component.
Dip Stick Tube - Painted steel is used for low cost and wear resistance. No external force acts on this component. It does not require a partiuclar shape as long as the dip stick is fitted inside, this part is bended from a tube. The shape and manufacturing process would be the same regardless the chosen metal. It is a functional component.
Dip Stick - Plastic and steel were used for low cost. No external force acts on this component. This component does not require a particular shape, and this part is cut out of a piece of metal. The shape and manufacturing process would be te same regardless the chosen metal. It is a functional component.
Oil Filter - The component is made up of steel and filter paper. No external force is applied to this component. This component does not require a particular shape, it is bended and cut from a piece of metal. The shape and manufacturing process would be the same regardless of the chosen metal. It is a functional component.
Distributor - Aluminum transfer electricity to the spark plug. Plastic insulates aluminum from other component of an engine. No external force acts on this component. This component does not require a particular shape, this part is molded plastic. The manufacturing prcoess would be different if it is not made by plastic. It is a functional component.
Distributor Mount - Aluminum is used for low cost, very little force is acted on this component since it just holds distributor in place. The process would be the same regardless of the chosen metal. Die cast is chosen because of high accuracy. It requires a particular shape depending on the distributor. It is a functional component.
Distributor Mount Gasket - Aluminum is used for low cost. No external force is applied to it. This component requires a partiuclar shape to hold distributor in place, so it is die casted for high accuracy. The shape and manufacturing process would be the same regardless the chosen metal. It is a functional component.
Spark Plug Wire - Copper is used for transfer of electricity, rubber and plastic insulates copper from other components. No external force is applied to it. It does not require a particular shape. The shape and manufacturing process would be the same regardless the chosen metal. It is a functional component.
Header Cover - Aluminum is used for low cost. It seals header, therefore some force created by combustion will transfer to it. This component requires a particular shape to do its work, so it is die casted for high accuracy. The shape and manufacturing process would be the same regardless the chosen metal. It is functional component.
Coolant Tube - Steel is used for low cost. No external force is applied to it. This component does not require a particular shape, so it is just bended and machined to desire shape. The shape and manufacturing process would be the same regardless the chosen metal. It is a functional component.
Oil Pump - Aluminum is used for low cost. No external force is applied to it. This component requires a particular shape, so it is partly die casted for high accuarcy. The shape and manufacturing process would be the same regardless the chosen metal. It is a functional component.
Oil Pan - Steel is used for strength. It is painted to increase wear resistance. No external force is applied to it. This component does not reqire a particular shape, this part is cut out from a metal and bended to desire shape. The shape and manufacturing process would be the same regardless the chosen metal. It is a functional component.
Piston Bearing - Aluminum was used for low cost, little force is applied to it since it hold connecting rod in place. This component requires a particular shape, so it is die casted for high accuarcy. The shape and manufacturing process would be the same regardless the chosen metal. It is a functional component.
Piston Head - Aluminum was used for strength. A high magnitude of force created by combustion process transfer through piston head. The shape of this component is very important. Die casted process is necessary for high accuracy becuase it has to be perfectly fit the cylinder. The shape and manufacturing process would be the same regardless the chosen metal. It is a functional component.
Piston Connecting Rod - Steel was used for strength. It transfers the force generated from combustion process to the crank shaft. This component requires a particular shape, and it is sand casted for low cost. The shape and manufacturing process would be the same regardless the chosen metal. It is functional component.
Crank Shaft Bearing - Aluminum was used for low cost. The rolation and virabation of crank shaft create a force acting on it. This component requires a partiuclar shape, so it is die casted and machined for high accuracy. The shape and manufacturing process would be the same regardless the chosen metal. It is a functional component.
Engine Block - It is the housing for internal combustion. Steel was used for strength since the expansion of gas would create an enormous force to the surrounding. This component requires a particular shape, so it is die casted and machined for high accuracy. The shape and manufacturing process would be the same regardless the chosen metal. It is a functional component.
Crank Shaft - Steel was used for strength. A large amount of forces acts on it from the cylinders. It requires a particular shape, it is sand casted for low cost. The shape and manufacturing process would be the same regardless the chosen metal. It is a functional component.
Rocker Assembly - Steel was used for strength and low cost, very little force is applied to it. It requires a particular shape, so it is die casted for high accuarcy. The shape and manufacturing process would be the same regardless the chosen metal. It is a functional component.
Push Rod - Steel was used for strength, very little force tranfers from crank shaft through push rod. This component does not require a particular shape, a piece of metal is cut to a desire shape to form this part. The shape and manufacturing process would be the same regardless the chosen metal. It is a functional component.
Coolant Valve - Steel was used for strength and low cost. No external force is applied to it. This component requires a particular shape, it is sand casted for low cost. The shape and manufacturing process would be the same regardless the chosen metal. It is a functional component.
Spark Plug - Porcelain and Steel were used for conduction of electricity. No external force is applied to it. It does not require a particular shape, this part is machined to desire shape. The shape and manufacturing process would be the same regardless the chosen metal. It is a functional component.
Metal Bracket - Steel was used for strength. No external force is applied to it. The painting process can increase its wear resistance. It does not require a particular shape, this part is cut out of large sheet and machined to desired shape. The shape and manufacturing process would be the same regardless of the chosen metal. It is a functional component.
Header - Steel was used for strength and low cost, very little force is actually applied to this bracket. This part is cut out of a large sheet and bent to the desired shape and then painted. This process would be the same regardless of the chosen metal, the shape of it determines what process was used to form it. It is a functional component.
Fasteners
| Name | Quantity | Material | Photo |
|---|---|---|---|
| 9/16" Nut | 8 | Steel | 
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| 13mm Nut | 7 | Steel | 
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| 15mm Nut | 1 | Steel | 
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| Cable Snap | 1 | Plastic | 
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| Metal Bracket | 1 | Steel | 
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| 13mm Threaded Rod | 3 | Steel | 
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| 15mm Threaded Rod | 5 | Steel | 
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| 15mm Bolt | 18 | Steel | 
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| 14mm Bolt | 3 | Steel | 
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| 13mm Bolt | 5 | Steel | 
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| 10mm Bolt | 20 | Steel | 
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| 8mm Bolt | 5 | Steel | 
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Design Revisions
- The first design revision is to expand the holes of the intake. Larger holes would increase the amount of air flowing into the engine, which allows for more oxygen to mix with fuel in the engine. This results in an increase in the engines horsepower and overall performance. If done by an individual this is a very simple and easy modification which will noticeably increase the engine's performance. For the manufacturer to make the change to the design requires a lot more work and will be fairly expensive. The manufacturer would have to increase the hole size in the intake pipes as well as in the engine block, and then create entirely new molds for each of these.
- Our second design revision is to increase the diameter of the exhaust pipes coming out of the cylinders. An increased bore size can greatly increase the flow of exhaust gases out of the cylinders, reducing the work done by the crankshaft to remove the exhaust and decreasing the amount remaining in the cylinder for the next cycle. Both of these things will increase the efficiency and thus the power output of the engine. This revision would require some simple design modification, increasing the hole diameter in the block for the exhaust and increasing the diameter of the pipes leading from the engine. This change would require a new mold to be used for the engine block, so it is a fairly costly change for them to make.
- Our third design revision is to increase the distance of the intake system to the engine block. This revision will decrease the temperature of the air being put into the engine which yields multiple desired results, power and efficiency. By lowering the temperature going into the cylinder we get a more efficient combustion process, yielding more horsepower from a given amount of fuel. This also means we get the same amount of power from a smaller amount of fuel, thus greater efficiency. This change does have the drawback of increasing the size of the assembled engine, but for most applications this would not be a problem.
Solid Modeled Assembly
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Of the many components of an engine to choose from we selected a piston for our solid model. A piston is a very key component to an engine, in addition to being one of the more commonly recognized parts of an engine to the average person. In addition due to our lack of any specialists in the field of 3D solid modeling it was convenient to select a part of moderate complexity, in order to solid model the part we needed to be able to transport the part which was easy being that we selected the engine piston. These reasons all factored into why we selected the piston for our solid model.
As for our selected CAD package, we decided to go with Autodesk Inventor. This was one of the most user friendly, easy to learn packages readily available. It has a free downloadable student version, giving members of the group access to the software from their own computers requiring people to go to a computer lab. Another reason we chose this was that members of the group had some experience with the software and With a downloadable student version available for free online, and group member would have access. In addition, we had people within access, with prior knowledge on how to use inventor which would also help our group in the long run.
Engineering Analysis
A problem that occurs relatively frequently in consumer automobiles is an oil leak. It could be caused by damage to any part with oil flowing through it or any point that is not sealing correctly and is allowing some fluid through. In either case the engine is losing vital oil and will tear itself apart if the level drops too low. Here we are evaluating how long it will take for a slow leak to reduce the amount of oil to a dangerous level. We are assuming that the speed of the leak is constant and unrelated to the remaining volume of oil. We are also treating oil as an incompressible substance
Starting volume of oil: 4.5 quarts (260 in^3)
Dangerous volume of oil: 2.5 quarts (144.5 in^3)
Hole diameter: 0.1 inches
leak speed (v): 1in/min
As can be seen above, even a very small leak can quickly reduce the volume of oil available in an engine to dangerous levels. The decreased volume will also tend to have a higher percentage of foreign particles in it such as metal shavings from metal wearing and soot from the cylinders. Depending on when the car last had its oil changed, the minimum safe volume of oil could be significantly higher than what we assumed for this problem due to the amount of junk mixed in with the oil.
Critical Design Review
Product Reassembly
We rated the difficulty of each step on a scale of one to five with one being very simple and five very complex. A complexity of one means that it was very straight forward to perform this step of reassembly. This means there were very few parts to reattach, they did not require special tools and positioning of the part is fool-proof. A complexity of five means that the part required special tools to reattach, part location or orientation was not sure even with excellent documentation, it may also mean that there were a large number of parts with slight differences among them.
| Step | Difficulty | Procedure | Notes | Image |
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| 1 | 5 | Push in 4 pistons with piston connection rod into cylinders | requires special tool to compress piston rings, must align connecting rods with crankshaft |
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| 2 | 2 | Attached journal bearing (4) to each connecting rod | nuts used are not hexagonal, hex sockets do work for this. Bearings do come out of their mounts fairly easily, may have to remove a part to get them back in |
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| 3 | 2 | Attached journal bearings (5) to the engine block | the one closest to the output is not the same as the other four |
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| 4 | 3 | Attached the oil pump | line up the pump using its bolt, lining up based on the tube is difficult |
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| 5 | 1 | Attach oil pan | nothing of note |
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| 6 | 3 | Flip over engine and attach header gasket and header | align the side with attached mechanisms with the output shaft |
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| 7 | 5 | put the push rods (8) in place then attach the rocker assemblies (8) | finding where the push rods sit is somewhat challenging, properly aligning rocker assemblies on springs and push rods takes some time |
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| 8 | 2 | put the header cover on and screw it in | 2 of the bolts are not the same as the others, the one with the wire clip goes on the bottom second from the right (oriented as in picture), the one with the bracket goes on the bottom left (oriented as in picture) |
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| 8 | 3 | screwed in the 3 spark plugs and attached the wires that provide power | requires deep sockets, normal ones do not work |
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| 10 | 1 | screwed the oil filter on | tightened by hand |
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| 11 | 3 | attached the intake | one tube is difficult to access to reattach, otherwise very easy |
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| 12 | 2 | attached the exhaust | nuts did not like to turn, requires deep socket. Must be done before coolant tube or dipstick can be done |
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| 13 | 3 | attached the coolant tube | one end goes into the front of the engine, the other end is not attached to anything, must be done prior to dipstick tube being put in place |
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| 14 | 3 | attached dipstick tube | nothing of note |
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| 15 | 3 | Attached distributor plate, distributor gasket and distributor | Correct alignment of plate is not obvious, distributor gasket is easy to forget about |
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| 16 | 3 | Attach wires from spark plugs to distributor | Order would be important if the engine was going to work |
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| 17 | 3 | Attach coolant valve | nothing of note |
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Reassembly Review
Q. Does your product run the same as it did before you disassembled it?
A. Without replacing a significant number of parts our engine is destined to remain a paperweight. Many of the parts have had sections cut away to allow a view of the inside, rendering them unusable. Among the cut open parts are the oil filter, the engine block, the oil pan and the headers. If we were to replace all of these parts it would most likely function, but due to the cost in time, labor, and parts it would be more economical to simply replace it.
Q. What were the differences between the disassembly/reassembly processes? Were the same sets of tools used? Were you able to reassemble the entire product?
A. We were able to entirely reassemble our product, everything went back together the way it came apart. For the most part assembly was identical to disassembly but in reverse. Putting the pistons back in took a special tool to compress the rings which was not needed during disassembly. Other than that one tool the tools used were identical. A combination of sockets and crescent wrenches enabled us to put the entire thing back together.
Q. Are there any additional recommendations your group would make at the product level (operation, manufacturing, assembly, design, configuration, etc.)?
A. The one thing that could be simplified would be the number of different socket sizes that are needed to handle all of the nuts and bolts. Often we would be working with one size socket and then the next set of bolts would require us to use the size 1mm larger or smaller. Simplifying their system so it only used 2 sizes instead of 5 would greatly reduce the number of tools needed to put the engine together. As a whole the product seems well designed and the process for manufacturing seems streamlined. There were a few spots on the engine where it looked like something could be attached, which we can only assume is due to this engine design being used for a variety of tasks. They could remove these unnecessary features but that would require a different mold for the engine block for other purposes.
