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Knocking noise and shifted timing belt - 88 manual

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Old 05-11-2021, 04:45 PM
  #16  
mhousny
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Angry

Here’s the footage, you can hear the squeaking noise in the middle and the like if teh belt is rubbing under the right cover

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Old 05-11-2021, 05:19 PM
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FredR
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That looks very wrong to me. Just follow Stan's recommendations- you will not go wrong.
Old 05-11-2021, 05:30 PM
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you wont be able to see the front edge of the pulley with the covers on,
on a 16 valve engine,.
You need to remove one bolt then the right cam tower cover will come free
Old 05-12-2021, 09:28 AM
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mhousny
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Default 928S timing belt issue

Guys, here are the pics with the cover off (kinda). It looks that it fits well. The left cam pulley though stll vibrates. You can here the squeaking noise coming from there (see the video bello). I think my mechanic tightened the belt too much. Let me know what you think.




Old 05-12-2021, 09:37 AM
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See

Last edited by mhousny; 05-12-2021 at 03:11 PM.
Old 05-12-2021, 09:40 AM
  #21  
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you need to remove the other right belt cover
Old 05-12-2021, 10:10 AM
  #22  
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Hi Stan,

I did, sorry I posted the same pic twice. The one I posted id the diver’s side, the footage is taken on the passenger’s side where the nose dome from:






Old 05-12-2021, 10:11 AM
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Footage :
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Last edited by mhousny; 05-12-2021 at 03:11 PM.
Old 05-13-2021, 07:11 AM
  #24  
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Guys, I went ahead and ordered a stethoscope from Amazon. As soon as I gets here I’ll check o that squeak and update you.
Old 05-13-2021, 10:24 AM
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Mrmerlin
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the right side belt picture looks OK.
I would replace the zip tie thats holding the green wire with another one thats more loose.
That squeak sounds like the idler bearing did it get wet? ( idler bearing is above the tensioner roller)
please remove the right belt cover and take a picture of the tensioner, also spin that bearing
Old 05-13-2021, 11:30 AM
  #26  
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Tnx Stan. Maybe the roller got wet when they removed the radiator hose. I will verify all that.
Old 05-13-2021, 12:24 PM
  #27  
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if the block was not drained via the block drains prior to removing the pivot bolt for the tensioner,
This will let a gallon of coolant come out the hole and flood that bearing.
Old 05-13-2021, 12:32 PM
  #28  
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That is certainly the issue. I have asked the mechanic back them if he drained the block by the two bolts and he said that he didn’t. He removed the radiator’s bottom hose only. Do you think I’ll need to replace the roller or its bearing now?
Old 05-14-2021, 10:30 AM
  #29  
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Guys, a quick update:
The stethoscope arrived today. I tried to listen on each bearing and the squeaking comes a bit from the right cam pulley and a but string from the tensioner’s roller. I guess Stan is right and the bearing got wet and are to replace .
Old 06-29-2021, 10:42 AM
  #30  
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Hi guys,
problem solved. I re,oved all the belts and the noise disappeared. I reinstalled the belts one by one till the last one.I replaced the ac compressor’s belt that was a bit too long and all is fine now.
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