Group 18 - GM V-6 Engine Gate4
Gate 4: Critical Design Review
- With the engine inverted the crankshaft was set back into its place in the engine block.
- The four crankshaft bearings (2 bolts each) were bolted to the block in order to hold the crankshaft in place. (16 mm socket wrench: 8 bolts total)
- With the engine in upright position each of the six pistons were pushed into their respective position. Note: Instead of using a piston ring compressor, screwdrivers were used to push the rings in one side at a time to allow the head to fully enter the cylinder.
- While the engine was again inverted the connecting rods were attached to the crankshaft via clamp bearings. (14 mm socket wrench: 2 nuts each)
- Now with the engine in the upright position the oiler was fed back into the bearings that held it in place in top of the engine. The flange bolt was then screwed in to hold it in place.
- The camshaft was fed back into the bearings that held it in place in top of the engine.
- The camshaft mounting bracket was bolted on with T-20 torx head screws. (2 screws total)
- The oiler drive gear was placed over top of the camshaft. This was followed by the camshaft’s timing gear and chain from the crankshaft with three bolts that held it in place. (13 mm socket wrench: 3 bolts total)
- The flywheel was reattached to the opposite side of the engine with six bolts. (14 mm socket wrench)
- The oil pan was then attached with 12 bolts (12 mm socket wrench) and then the oil cooler adapter with 2 additional bolts. (12 mm socket)
- Next, the 12 rockers (AKA lifters) were put back into place riding on the camshaft, followed by one rocker cover per side. (10 mm socket wrench: 2 bolts each)
- Each head was bolted into place with 12 bolts per head. (13 mm socket wrench)
- The 12 pushrods were replaced and the valves were realigned to rest on top of the pushrod and valve spring. The valve nuts were tightened with a 13 mm socket wrench.
- The camshaft cover was replaced on top of the camshaft sprocket and timing chain area. (6 point flange bolts: 6 total, 1 was missing)
- Using a hammer, the harmonic balancer was pushed back into place.
- The crank pulley was bolted to the harmonic balancer using 2 bolts (14 mm socket wrench: 3 bolts total, 1 was missing). Then, the water pump was bolted to the block. (14 mm socket wrench: 4 bolts total)
- The intake manifold was then reattached to the block. (14 mm socket wrench: 10 bolts total)
- The 2 valve covers were attached to each head with 6 bolts each. (13 mm socket wrench)
- The 2 exhaust manifolds were then bolted to the block with 10 bolts each. (14 mm socket wrench)
- Next, the fuel injector lines were pushed back into place by hand.
- Then, the upper intake housing was bolted on (12 mm socket wrench: 6 bolts total), followed by the distributor (10 mm socket wrench: 2 bolts total).
- Finally, the throttle body was replaced with 3 bolts. (10 mm socket wrench)
- From the beginning the product was never in a state to fully test its functionality since it is missing several crucial components such as emf source, fuel tank, radiator, and alternator. During the disassembly many flaws were discovered to infer that the engine is not in a running condition such as a crack in the intake manifold and faulty piston rings.
- The reassembly process was very similar to the disassembly. The major difference was for the disassembly we needed a pulley puller that was not required for reassembly. To reattach the harmonic balancer there was force required, this was done so by means of a hammer to push it back in place. Also for reassembly screwdrivers were used in place of a piston ring compressor to feed each piston head back into a cylinder. Other than these differences in tools, all other tools were the same and the product was successfully put back together.
- An additional recommendation at the design level of the engine would be to take greater effort in making bolt size uniform throughout the whole engine. Also, it may make more sense to manufacture bolts in solely customary or metric sizings, as opposed to a combination of both. By standardizing bolt size, disassembly and reassembly would be considerably easier and faster. Most bolts are 10 to 14 mm in diameter, a close enough range that making them all the same size would be feasible. However, it could be slightly more confusing to determine which bolts go where when diameter is no longer a differentiating factor.
Return to Group_18_-_GM_V-6_Engine