98 Sunfire with 2.4L somehow jumped time and bent all the intake valves. First thought was that the tensioner (1-piece spring type) failed. Valve job has been completed and everything is put back together with the exception of the timing cover because of the following:
I installed a new tensioner, got the timing set, released the tensioner and everything is tight. When I turn the crank, the piston in the tensioner extends outward a little bit. If I turn it a little more the piston in the tensioner goes back in a little bit . A little more and then I get slack between the two camshaft sprockets and also between the intake sprocket and the crank sprocket. I keep turning and slack disappears as the piston in the tensioner extends outward again. Process continues as I crank...
Has anyone seen this before? I'm thinking that a section of my timing chain is stretched and causing this scenario. When the stretched section of the chain gets to the tensioner, the tensioner extends to take up the extra length, but once the stretched section goes over the exhaust cam sprocket, I see slack in the chain. Does this make sense?
The chain was replaced about a year ago (along with the tensioner) when I did a water pump change. I wasn't thinking that I should need to replace the chain again so soon, but this problem is making me think otherwise.
I'm going to go pick up a new chain and all new sprockets tonight and see how things go tomorrow night. I'll post my results, but in the mean time, I was hoping maybe someone else has experienced this and might have some input.
Problem solved... I believe the old chain was streteched causing slack between the intake and crank sprockets. Everything is put back together and running, but engine is running pretty rough.
Would this minor difference in length cause that much slack?
Yes it could cause slack, but if you timed the motor correctly the slack would be at the tensioner and not between the cams. now once everything is timed and set, and then you turn the crank moving the motor over. You will see some slack in between the cams. This is normal. This has to do with compression, and the cams turning. When you turn the motor over and put it back to TDC (Top Dead Center) is there slack?
FU Tuning
