I have a 2001 cavalier, it has 117k mi on it %26amp; i havent replaced it yet. when should i change it %26amp; is there any warning i get b4 i goes 4 good?
When should i replace a timing chain?
You should replace the chain/gears when there is more than a few degrees of play in the assembly.
To check it: rotate the motor (by hand) till you reach TDC. Remove the distributor cap. While watching the distributor shaft (rotor), turn the motor backwards until the distributor shaft begins to turn. Then note the amount that you were able to rotate the crankshaft... I cannot remember the specified amount that is acceptable at the moment (the reason I said a few degrees). There is an actual spec for this.
With that said, I have put over 200k miles on multiple vehicles without replacement of the timing chain.
When should i replace a timing chain?
do it now...even on a non interference engine letting go at high speed can damage engine [and leave you stranded usually on a rainy night far from home!!]
Nope no warning and if it quits it will likely cause lots more damage, go ahead and change it I think the general recommendation is 50 70 k miles
Don't listen to any of them.
Yea, it is smart to change it and its usually after 100K miles. But if you are going to change that, you need to go ahead and do an overhaul on the whole engine. Because in the long run, the cost to have the timing chain replaced is going to be with-in reason%26quot;depending on how long you are keeping the car%26quot; of cost... that you should just overhaul the whole engine. Unless you're going to do it yourself.
But why dismantle half your engine to replace one part when, while your into it, you can replace multiple parts.
The timing chain/gears will go forever, or they could fail. No warning. However, wear on the timing chain/gears can create rough-running engine or rattling noise. I've had timing gears fail at 200K miles (not a Chevy Cavalier), and the engine timing went off because the chain jumped a tooth on the gears. If you can afford it, it's good to replace them as a part of a full maintenance/rebuild after 100K.
I would wait for the chain and gears to start rattling at idle. When it starts doing that , plan on getting a new chain-gear set and tensioner for it.
