Group 9 - GM Inline Four Cylinder Engine
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Executive Summary
Group 9 received a 2.2 liter 4 cylinder gm engine for their reverse engineering project. The engine was nonoperational when received but otherwise in good condition. This project was completed in cooperation with group 24. The engine was divided amongst the two groups with group 9 being responsible for the belt drive system, camshaft and crankshaft. Group 24 on the other hand was responsible for the headers and pistons. The project was to be completed over the course of a semester and was broken down into 5 stages or gates.
Gate 1 is the Request for Proposal. In this a work proposal is laid out. The work proposal discusses the overview of the work plan, the tools and time required, and the group's capabilities and shortcomings. Gate 1 also lays out a management proposal. The management proposal gives an overview of the management plans. This lays out the responsibilities of each member and the role they will play. This also assigns each person a leadership role based on their expertise. Meeting times are also planned out as well as a plan to resolve conflicts. Gate 1 also deals with the initial product assessment. This is where several questions about the product are answered based on an initial assessment.
Gate 2 is the Preliminary Design Review. This is where the product is dissected and documented with images illustrating how the engine was taken apart. A difficulty is assigned to each task as well as details whenever difficulties occur. A cause for corrective action is also here detailing further how problems were resolved and how well the previously discussed plans (management and work) played out.
Gate 3 is the Coordination Review. Here each part is analyzed in detail post disassembly. Each part is analyzed in terms of function, shape, material, manufacturing process, and the forces acting on it. Upon analyzing the parts design revisions are proposed to improve the product. To increase the thoroughness of the review certain parts were solid modeled while others were analyzed with engineering analysis.
Gate 4 is the critical project review. This is where the product was reassembled while keeping the same level of detail as when the product was dissected. At this point the product was reevaluated compared to before the disassembly.
Gate 5 is the delivery. This includes finishing the wiki accompanied by a compliance matrix ensuring the completion of all parts. This stage also encompasses an oral presentation of the results of the project.
The project was successful in achieving the outlined objectives (as outlined in the introduction). The product was disassembled and reassembled successfully while being analyzed along the way. Below are the results of this project.
Introduction
The main objective of this project was to dissect and analyze an assigned product. Group 9 was given a 2.2 liter 4 cylinder gm engine. The engine was nonfunctioning upon the start of the project. Understanding how products work and how to apply engineering logic to real world products is a very important skill to develop for engineers. This project reinforced these key skills as well as allowed for the improvement of group working skills. This project also gave a chance to showcase technical writing skills and decision making skills.
Gate 4: Critical Project Review
Product Reassembly Plan
Group 9 begins their reassembly process with an empty engine block; their tools which includes a socket set, rubber mallet, and Torx screwdriver; and all of the disassembled components mentioned below. For each step a difficulty from 1 to 5 was assigned; one being the easiest, task accomplished with little effort, and five being the most difficult with many attempts required to perform the task correctly.
| Step | Procedure | Difficulty | Image |
|---|---|---|---|
| 1 | Reattach the water pump with (2) 13 mm bolts using a socket. | 1 |  |
| 2 | Reattach the water pump pulley with (3) 13 mm bolts using a socket | 1 | .JPG) |
| 3 | Replace camshaft by hand by inserting it into the slot and fixing it in place with a rubber mallet. | 2 | |
| 4 | Reattach the oil pump drive by twisting it into slot by hand. Insert (1) 10 mm bolt to secure it with a socket. | 1 |  |
| 5 | Reattach camshaft plate with (3) 10 mm bolts using a socket. | 1 |  |
| 6 | Reattach camshaft gasket with (2) Torx screws using a Torx screwdriver. | 1 |  |
| 7 | Reattached timing chain guide. | 2 |  |
| 8 | Insert the crankshaft and timing chain cover simultaneously while ensuring to fit the peg of the camshaft into the gear of the timing chain. | 5 |   |
| 9 | Reattach timing chain cover with (6) 8 mm bolts and (1) 1 inch bolt onto the gear using a socket. | 1 | |
| 10 | Reattach idler pulley with (3) 16 mm bolts and (1) 19 mm bolt using a socket.. | 1 |  |
| 11 | Reattach the serpentine belt tensioner with (1) 16 mm bolt using a socket. | 1 |  |
Reassembly Analysis
Does your product run the same as it did before you disassembled it?
When we were assigned the GM inline four cylinder engine as our product, it was not in working condition. After reassembling the product back to its original state we were able to rotate the crankshaft with all of its connected parts rotating simultaneously as well. This made sure that the product was in the same running condition as assigned initially.
What were the differences between the disassembly/reassembly processes? Were the same sets of tools used? Were you able to reassemble the entire project?
For the most part, the disassembly and reassembly processes were almost exact but in reverse order except for a few alterations. Reinserting the crankshaft turned out to be a very difficult procedure and quite different from how we extracted it in the disassembly. When dissecting the engine, the crankshaft had to be maneuvered and removed by hand which did not prove to be very difficult. Reassembling it however, was a precise and tedious process. The heavy weight of the crankshaft and timing chain cover component complicated things when we tried to reinsert it and had to align it exactly to fit correctly. It was also slightly tricky to match the timing chain gear to its chain correctly while simultaneously placing the crankshaft in its slot. Besides the addition of the rubber mallet, the same tools were required for the assembly of the engine which includes a set of socket wrenches and a Torx screwdriver. After approximately three hours, Group 9 was able to successfully reassemble our half of the engine just as we were presented with it.
Are there any additional recommendations your group would make at the product level (operation, manufacturing, assembly, design, configuration, etc.)?
The main recommendation Group 9 is suggesting for the GM 2.2L 4-cylinder inline engine is an overhead camshaft configuration. As mentioned in the design revisions an overhead camshaft configuration is more efficient and produces more power than an in-block camshaft. Also, disassembly and reassembly of the camshaft and its surrounding components is much more difficult than an overhead mounted camshaft. Group 9 experienced the difficulties of reassembly when the camshaft would not line up properly with the timing chain gear. It is much more difficult to make adjustments when the camshaft is sitting deep inside the engine block than sitting on top of the headers. Group 9 had to make small adjustments to make the timing chain gear fit on the end of the camshaft and it would be easier to adjust on the outside of the engine block.
