Engine Knock Vs. Timing Belt Tensioner

[SilverBullet75]

http://www.vehicross.info/forums/sho...t=10722&page=3

A HUGE THANK YOU TO COWBOYERIK!!!!!!!!!!

I've been in a VX depression ever since I heard that darned knocking sound in the motor. I even warned my wife about the "potential" of the motor going kaput long ago. After reading CowboyErik's post, I felt I had hope still. Sure enough! I pulled off the passenger side timing belt cover enough to push on the belt. Without any trouble at all I was able to deflect it by almost an INCH! So, after about 45 minutes I had the front end torn apart and found that the timing belt tensioner went bad!!! I can plunge the piston with my hands with ease, and there is oil leakage around the "pushrod" base. (see pics).
SO, IF YOU THINK YOU HAVE ROD KNOCK/ENGINE FAILURE, CHECK THIS BEFORE SENTENCING YOUR VX MOTOR TO DEATH!!!!

[Ldub]

This is good info., I've heard of this on the 3.2(mostly sohc?, not sure), but this is the first I've seen of it on the 3.5.
Thanks to Cowboy Eric & Silver Bullet 75.

[Ebenezr]

WOW! So this could be my number 1 cylinder Knock! I have been bracing myself for several months now for the engine to DIE.

[SilverBullet75]

If you take the timing belt covers off, you should be able to deflect the timing belt pretty easily by hand. If this is the issue, you just saved $k's!

[cwmoser]

WOW! So this could be my number 1 cylinder Knock! I have been bracing myself for several months now for the engine to DIE.

Ebenezr ... I have a knock that appears to be on number 1 cylinder too.
Did you check your Tensioner? If so, what did you find?

Thanks

Carl

[BigSwede]

On the 3.2Ls, a diagnostic for the timing belt tensioner is if the knock goes away at higher rpm, above 2000-2500 rpm. But it can definitely sound like a death rattle, when my tensioner went out at Moab, everybody who heard the motor looked like they were at a funeral. But instead it was a $65 part.

[Ebenezr]

I can't get to it. Prying the cover back I can't do. When I put a stethascope on it the tap is loudest coming from the timing cover top bolt which enters right into the no. 1 area in the head. It will have to be torn apart to check but for the engine runs great. I am going to rev the engine today like BigSwede said and see if it disappears.

[cwmoser]

I can't get to it. Prying the cover back I can't do. When I put a stethascope on it the tap is loudest coming from the timing cover top bolt which enters right into the no. 1 area in the head. It will have to be torn apart to check but for the engine runs great. I am going to rev the engine today like BigSwede said and see if it disappears.

My engine tapping goes away above 2500 rpms too and the engine runs great.
I need to open the timing covers and take a look see too.

Carl