Group 18 - GM 2.2 Liter 4-Cylinder Inline Engine - Gate 4
Contents |
Project Management: Critical Project Review
Cause for Corrective Action
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
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
- Nearly all of the steps within the reassembly procedure are similar to the disassembly process. Only a few steps require a bit more work but overall the concept does not differ.
Day 1 (Wednesday, 11/30/2011)
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)
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).
Original Assembly
The original assembly process in the factory is an inside-out assembly way, which means the assembly will start from installing the pistons then the crankshaft followed by the camshaft, and finally, other parts that are located inside the engine cylinder block before moving out to the external part like intake manifold and exhaust manifold. The tool that the factory used in the original assembly is more sophisticated compared to the tools Group 18 used in the sense that they have a more specialized tool for installing more complex parts like the valve spring and inserting the piston (with piston rings) into the cylinder block. Apart from that, the original assembly line mainly relied on manpower with basic tools such as a wrench.
Design Revisions
- To implement the OHC system, the design of the engine head block will have to be changed since the camshaft will be located in the engine head block instead of the engine cylinder block. However, the manufacturing process will still remain the same, which is die casting. Besides that, the timing belt will have to be changed from chain belt to rubber belt since rubber belt produces less mechanical wear per unit length. With the increased length of the timing belt, the timing system will also be more complex and, therefore, a few more sprocket will need to be added to ensure that the timing is always accurate. 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.
