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Car wasnt running good so I just removed my valve cover to inspect the timing chain, the chain is sagging between the two gears, so there is slack on it, should there be any slack at all or should it be tight, what should I do. Could it be the tensioner worn out, if it is the chain and needs to be replaced, do I have to replace the two gears too? Please help I am working on the car right now in my yard :zoinks:
 

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As no one's replied yet, and I have never replaced an SR20 chain, but I've lots of experience of the things on motorcycles inside and outside engines, I'll pass on a few bits of info.

To check the gears, just look at the shape of the teeth, when they are worn they develop a hook shape where they've worn in the middle of the tooth. To check the chain (and gears if they're very bad) temporarily tension each chain run either side of a gear so there's zero slack and then with finger and thumb try to pull the chain off the middle of the gear run. The chain should barely move, if you can lift it, it's badly worn.
 

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could be the tensioner......mine was shot and had to be replaced a lil while ago
 

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^^^ yup, i would suspect the tensioner. turb the crank with a socket while the valve cover is off and see if the slack dissapears. and take out the tensioner and inspect it to make sure its working. the tensioner is suppossed to not let any slack exist, otherwise you can skip a tooth and bend a valve(seen it happen already)
 

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It could also just be how the cams are lined up... if they have tension from the valve springs in the right direction, it could allow everything to line up with some slack between the two cam gears. You'd want to make sure and have the motor at TDC, etc..

Now, if there's slack between the cam gears and the gear on the crank too, then you'd probably have tensioner issues.
 

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JustinP10 said:
It could also just be how the cams are lined up... if they have tension from the valve springs in the right direction, it could allow everything to line up with some slack between the two cam gears. You'd want to make sure and have the motor at TDC, etc..
I dont know about you justin, but ive never seen a slack chain when pulling the VC. The only time that chain will go slack betweent the gears is if you manually crank the crank bolt back a bit.
 

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Yahnozha said:
I dont know about you justin, but ive never seen a slack chain when pulling the VC. The only time that chain will go slack betweent the gears is if you manually crank the crank bolt back a bit.
Yeah, I guess I was just remembering back to when I did a few valve adjustments and other stuff on various cars, or where I'd have to adjust the cams manually, to get everything to TDC w/ the marks on the chain showing, before installing cams... As I'd rotate the cams through the whole cycle, the tension would change, depending on how the cam lobes were in relation to the rocker arms.

Yeah, normally there should be some tension between the two gears...
 
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