Cam tensioner gone bad?

[reminor]

I have just checked my cam chain tensioner and it looks like it binds. Clymer manual says the way to check the tensioner is to push on the plunger. The plunger should move back and forth. I tried but no matter how hard I pressed with my hands the plunger never moved. When I wind the spring the plunger retracts enough so I could install it. But as soon as I release the spring the plunger returns back to fully extended position and locks up there.

I am in doubt - is my tensioner bad? Please advice.

TIA

[sanjay]

The fact that it doesn't retract when you push on it means that it DOES work.   

Its purpose is to keep the chain under tension regardless of chain stretch.  So you install it, and as the chain stretches over time, the tensioner automatically extends.  The only way it can retract is by hand.

Try winding it, holding the plunger in with your hand, and releasing the spring.  It should be hard to keep in, and when you let it out bit by bit, it shouldn't allow you to push back in.

[The Buddha]

Press in the locking clip and push it in, that should let it retract but may be tight and slow and weird feeling, cos it has to turn a spring at the other end. if you're not careful, you can end up with a spring that has sprung out of the back side.
Cool.
Srinath.

[reminor]

Thanks for clarifying that for me. Now I know it works as designed. Thus Clymer service manual is wrong (ISBN 0-89287-759-6, page 116, Camshaft Chain Tensioner inspection):  "Push in on the plunger (B) and then release it. The spring should offer resistance when the plunger is pressed in. The plunger should move in an out with no binding."
Beware!