Pontiac 10101790 Gear Set, Cam And Crank, Matched

If an engine has been removed from the car, some of the procedures described below should be ignored as well. First of all, you should degrade the torsional damper and the crankcase cover. Next, rotate the engine until that mark on the sprockets matches the other so that both sprockets and the chain cannot be removed from the engine in the wrong position. Then, take out the three camshaft sprocket retaining bolts and raise the camshaft sprocket and the timing chain up from the front of the engine with a tap of a soft-faced mallet if require. In the case when the crankcase sprocket has to be removed, use a puller which is designated for such operations. Fit the crankshaft sprocket to the crankshaft with a bolt and washer of the puller set. Next drop in the timing chain onto the camshaft sprocket with the slack downwards over the crankshaft sprocket. Slide the chain over the crankshaft sprocket, then bring the camshaft sprocket home with the three screws on the front, using a lot of care that you do not hammer since you can knock the freeze plug at the back of the engine. After the chain and both the sprockets have been fitted, ensure that the marks on the two sprockets coincide but if they do not, then the camshaft sprocket should be removed again to facilitate the alignment of marks. Last but not the least, apply the engine oil on the chain and put back all the parts in reverse manner that they were dismantled.

Lose the cable from the negative battery terminal and thereafter, remove the vibration damper and the crankcase front cover. Nishino also said before removing the chain and sprockets examine the sprocket teeth for being wore down and the chain for looseness. If any sprocket exhibits sign of wearing, they should be replaced. A timing chain that one may not have changed earlier or has more than 25,000 miles on it, will require replacement as any inaction on the same may result to superfluous shaking and shivering of the engine, and least miles per gallon. Camshaft sprocket, crankshaft sprocket and the timing chain if any of them are worn out, then all of them are replaced. In order to start with removal, rotate the crankshaft so as to align the timing marks on the cam and crank shafts such that number one and four pistons are at the top centre. Loosen the three camshaft sprocket retaining bolts from inside with a screwdriver and a breaker bar to such an extent that you may require to tap the sprocket with a soft-faced hammer. Should the camshaft be pulled, endeavour to lift the sprocket off the dowel pin; otherwise, the crankshaft sprocket must be unbolted and pulled off. After that, unscrew the old crankshaft sprocket from the crankshaft and, after that, screw on the new crankshaft sprocket on the same crankshaft but making sure it matches the key. Oil the tw4o contacting surfaces of the camshaft sprocket and then make sure that the two tabs of the timing mark engage with each other as the chain is pulled over the sprockets. Put the camshaft sprocket on the camshaft while tightening the retainers of the sprocket without using hammering technique. Check that the timing marks are lined up if not reposition the camshaft and repeat the same until they are in order. Last of all, pour engine oil on the chain and then reverse the sequence to replace every part.

The first step is to remove the rocker arm cover.

Clean all surfaces and check for distortion on metal covers, restoring the gasket surface if necessary.

Temporarily install the sprockets and turn the crankshaft until the number one piston is at Top Dead Center, ensuring the camshaft 'O' mark is straight down and aligned with both shafts.

Place the timing chain over the camshaft sprocket, allowing slack to hang down over the crankshaft sprocket.

Install the timing chain over the camshaft sprocket, allowing slack to hang down over the crankshaft sprocket.

The final step is to lubricate the chain with engine oil and install the remaining components in the reverse order of removal.

After aligning the timing marks, remove the three camshaft sprocket retaining bolts and lift the camshaft sprocket and timing chain together off the front of the engine, tapping the sprocket with a soft-faced mallet if necessary.

Do not remove the sprockets or chain until the alignment is confirmed, and avoid turning the crankshaft or camshaft afterward.