Timing belt tensioner question

[sho 'nuff]

Should be the bolt attatched to the tensioner be spinning or is this a sign that the bearings in the tensioner are shot? The bolt itself seemed to be tightened down all the way. There is quite a bit of slack in the timing belt and its making the tell-tale knocking type noise. Am I looking at replacing the tensioner or do I just need to adjust it?

 

[sdpatt]

If you are referring to the tensioner in your 3.2L engine, the nut on the bolt in the tensioner pulley's hub should be torqued and not spinning. The bolt on the tensioner lever arm should also be torqued to spec and not moving. Is the gas piston providing significant pressure to teh lever arm? If not, it is the problem. If either of those nut/bolts are freely turning, something is stripped and may need repair or replacement. Relly need more information to know exactly what you are describing.

 

[sho 'nuff]

I borrowed your picture to point out the bolt that seems to be spinning. This bolt was spinning How do I determine if the piston arm is providing enough pressure? From observing the timing belt with the car running, there seemed to be slack(up and down movement of the belt) across the top, between the two cam sprockets(I think I am using the correct terminology) but on either side it seems to be tight. Does that make sense? This was the first time I've had the timing belt cover off so I'm far from an expert here.

 

[sdpatt]

That bolt should not be spinning, but instead, torqued to secure the hub of the pulley. This bolt is not removed to replace the timing belt and should be left alone to maintain the eccentric hub in the original orientation to maintain the tension set by Yamaha. Only the two bolts securing the gas piston are removed to release the tension on the timing belt during the belt swap.

It is most likely that the threads in the aluminum tensioner lever arm are stripped where that hub bolt is attached. That will require either a Heli-Coil type thread repair or a replacement lever arm.

The tensioner piston should require a C-clamp or vise to compress the piston to align the small holes so that a 1/16" drill bit, Allen wrench or nail can be inserted to hold the piston in the compressed position. I don't have a number on the pressure needed to compress the piston, but it should not move with hand pressure. It should take the C-clamp or vise to compress the piston.

 

[SHOguy 92]

if the bolt is spinning it has to be either tightening which would cause the tensioner to not spin. or losen where it comes off and so would the tensioner. so if its just spinning doing nothing i think that means its stripped i ain't sure just my guess. and whiule im at it im guessing sdpatt will come back to this post so i was hoping you'd go heck out the Gen 1+2 engine mod board and read the electric water pump idea, i figured if anyone would know if this was a good i dea or not i'd be u and maybe was hoping u knew where to buy a kit. but anyways good luck with the tensioner problem.

 

[projectSHO89]

Just make sure that you understand that the part you indicated (for purposes of acquiring a replacement, if required) is the idler for the tensioner, not the tensioner itself.

Best of luck in finding a new one. our best bet will probably to locate a used one.

Same for the tensioner itself if it fails the tests that Scott indicated.

Steve

 

[sho 'nuff]

Scott thank you for the explanation. Those Autozone links you posted are sure coming in handy!

Thanks for the clarification Steve thumb

Fred actually had both pieces used so I went ahead and sent him money for them...and I'll just sell whichever one I don't end up needing.

<small>[ October 13, 2003, 12:47 PM: Message edited by: sho 'nuff ]</small>

 

[sho 'nuff]

*update* Well yesterday my friend Robbie and I got the timing belt covers off we could not determine which part seemed to be defective, but since I got both parts used we went ahead and replaced both. Whatever was wrong with the belt tension is now fixed though. No more slack and we also fixed the timing. Not sure if this happened when we switched out the parts or what, but the cam sprockets were not in alignment. When one sprocket was lined up at 12 o'clock, the other was more around 1 or 2 o'clock. Also wanted to note that the crank pully was lined up at 5 o'clock when one of the sprockets was at 12 o'clock, before everything was fixed.

Once we got that fixed and put everything back together... eek! It sounded like a whole different car when I started it up. Idle was a lot smoother and no more belt slapping either. Opened her up on the way home and was very impressed with the way it felt. I think I may have found those 10-15 horsepower my dyno seemed to be missing. Could having the timing off cause such a problem?

 

[projectSHO89]

You need to go back in and put BOTH cams at 12 o'clock. It sounds like only one of your cams is now properly timed.

Setting both of them to the prper timing will definately make s difference. The loose timing belt would explain having lost a significant amount of power.

Steve

 

[sho 'nuff]

I guess I worded that wrong. What I was trying to say is that everything was fixed and realigned before we put it back together. Once we found out it was misaligned, we loosened the belt and fixed the one cam sprocket that was out of whack. So the two cam sprockets were both at 12 o'clock and the crank at 5 o'clock. We followed the pictures that Scott had posted previously on the board.

 

[sdpatt]

With the white marks on the belt lined up with the three index marks at the pulleys and the timing cover/oil pump as shown in those photos, the camshaft timing is correct.