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SpeedyMitch
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I changed the timing belt and belt tensioner bearing about a year ago. I have put several *thousand* miles on the JH since then with no (related) issues. At one point Kurt confirmed that my belt was *slightly* on the tight side but pretty good (no belt noise).

Recently I noticed that the belt was wearing strangely. The side of the belt facing the engine would fray and wear making my 1" wide belt something closer to 7/8". Until last week the belt would be right in the middle of the pulleys every time I popped the hood to check it out.

Last night I took the belt tensioner off to check the bearing - all good. The belt tensioner has a lip on the inside that is causing the wear on the belt when the belt is running hard against it.

I installed a new timing belt and noticed right away that at idle the new belt moves all the way back on the pulleys, close to the engine block. I also noticed that the exhaust pulley has a wobble. I'm sure they are related as the wobble seems more pronounced than previously.

The exhaust pulley bolt is tight and the pulley itself does not have any apparent play.

Any ideas on probable causes for the pulley to wobble?

Thanks in advance for any ideas or assistance!

Speedy Mitch

Brett Gibson JH5 20497
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Mitch, I think I would pop that pulley off and check the seating if that looks Ok best bet would be to replace it.

As for the belt, Ive seen were they will ride on the front of the pulleys and also the backs, I think it has something to do with weather the tensioner is running on the up side or back side of the belt, I'd try both positions to see which one gets the belt away from scrubbing. Also if your pulley teeth start getting a shine to them even if you have no noise the belt is to tight.

Brett

SpeedyMitch
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> I think it has something to do with weather the tensioner is running on the up side or back side of the belt

Good thought. I have the tensioner on the up side now. It looks like the tensioner would be better centered if moved to the down position. I'll try that and let you know if it changes anything.

If I get some time I'll remove the pulley and check it for wear. I would guess any wobble in the pulley would be caused by wear at the shaft?

SpeedyMitch
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Is it possible for the tensioner pulley stud to have play in it? Does the stud screw into the block or is it pressed in?

Thanks in advance,

Speedy Mitch

Brett Gibson JH5 20497
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Mitch the later tensioners (single fat ones) use a stud that screws in and out, also NO play.

Brett

SpeedyMitch
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Brett Gibson JH5 20497 wrote: Mitch the later tensioners (single fat ones) use a stud that screws in and out, also NO play.
Thanks for the info Brett.

I have an early block (VIN 12827) but the PO updated the tensioner to the later style. I'll stuck a jam nut on there and see if I can get it to budge.



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