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Timing Belt Wear Question UPDATED 2-4-07

 
Old 02-04-2007, 01:52 PM
  #76  
Schocki
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Roger,
How does the bolt look if you roll it slowly over a very straight surface (like glas)? Is it really straight?

Looks like there is no visible wear on the rear portion of the cam gear that drives the camschafts. Looks like the belt was always running this far forward... strange
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Old 02-04-2007, 02:02 PM
  #77  
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Roger
I noticed the same thing on one we did last year.....we we put it back together we put one washer on the wrong side of the idler pulley it was just enough to through the belt forward (like yours) & it even ground on the harmonic balancer......did you note where the washer was when you removed it?
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Old 02-04-2007, 03:18 PM
  #78  
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Schocki,
Straight when rolled on glass. If it is bent in any way it is a couple of thou only.

Brian,
That was my first thought as the unworn portion of each roller is equal to the size of the large washer on the pivot bolt between the idler pulley and the carrier.
I checked against PET and everything seems in the right place.
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Old 02-04-2007, 03:20 PM
  #79  
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Rick,
I have all the symptoms you had but in the earlier stages it would seem.
I still cannoy understand why the TB is riding off the pulleys. By the wear they have been like that from the start.
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Old 02-04-2007, 03:20 PM
  #80  
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The wrong washer option is probably the cause. I was just wodering about the yellow paint on one of the cam gears. Seemed untouched after 1500 miles the paint should be gone for sure.
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Old 02-04-2007, 03:21 PM
  #81  
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I was going to agree with Schocki, but the cam gears look new all over, so no old wear tracks. Are they new?

I've had one 86 where I ended up with the belt tracking forward and hanging slightly off the front of the tensioner pulley, but not this much and not wearing on the front edge like this. I took it apart two additional times and could not figure it out. Isn't that encouraging?

The WP could have the pulley set forward for some reason, forcing the belt out. See where the belt is riding on that pulley. This is the only pulley in the system with edge walls and if the belt rides forward on both cam gears, it would be suspect. If the belt is being forced forward by the tensioner pulley misalignment, the passenger side is affected more than the driver side, so the path is more forward on the passenger side cam gear, while the driver side stays centered. Oh, and you could imagine that if the WP pulley axis were somehow canted up, that this would cause the belt to run forward, but I don't see how that could happen.

This looks so far off, I wonder if there might be some model year part mixups that could result in this. I can't remember if mixing parts can do this. Garth went through the various tensioner arms in a post long ago and seems to know the most about this.

Last edited by Bill Ball; 02-04-2007 at 03:40 PM.
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Old 02-04-2007, 03:23 PM
  #82  
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If it's straight, it's straight. On to other culprits.
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Old 02-04-2007, 03:31 PM
  #83  
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Roger,
Does the TB run against the WP roller notch? If you have an old WP lying around, measure the distance of the notch towards the WP housing and compare. The WP roller notch is the only thing that keeps the TB from falling of the gears anyhow. If I'm not wrong (haven't looked at mine for a while). Could it be a incorrectly assembled rebuilt WP?
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Old 02-04-2007, 03:43 PM
  #84  
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The cam gears are looking very good with very little wear on them as is the oil pump gear.
No records of these being changed.
The TB & WP job 1500miles ago states very clearly that the only things changed were the WP & TB. No other parts and the parts cost and labor seem to bear that out.
The tensioner has not been touched at all and the rollers are not new and probably original.

Here's the roller assembly as it came off the car.
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Old 02-04-2007, 03:46 PM
  #85  
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WOW, is that belt wear pattern off-center on the roller!

Did you get a look at the belt position on the WP pulley as Schocki and I mentioned, before you removed it?

The lack of any wear pattern on the cam gears is odd if they weren't replaced. The wear pattern on the roller suggests the belt has been doing this longterm and a new WP with something amiss with the pulley alignment wouldn't be the cause. Still, the fact that the whole belts rides forward points to it.
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Old 02-04-2007, 03:49 PM
  #86  
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The bolt that holds the washer is only for picture demonstration purposes, correct?
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Old 02-04-2007, 03:52 PM
  #87  
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Here's what mine looked like. Yours doesn't look bent.

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Old 02-04-2007, 03:55 PM
  #88  
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Bill,
Go back and look at the pics in post #67 and that shows the TB on the idler roller.

Schocki,
No thats the pivot bolt - pre 87 has a bolt.

Is that washer the right one? On PET it just gives a part number and no size.
The size of the un-worn parts of the rollers seems to equate to the thickness of that washer.
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Old 02-04-2007, 03:58 PM
  #89  
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Originally Posted by Schocki
The bolt that holds the washer is only for picture demonstration purposes, correct?
??
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Old 02-04-2007, 04:04 PM
  #90  
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Originally Posted by ROG100
Bill,
Go back and look at the pics in post #67 and that shows the TB on the idler roller.
Yes, I saw that it was forward on that as well. The belt is forward throughout its entire length.

That thick washer appears to be correct for 85-86. It appears the arm and roller is located OK, but the belt isn't.
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