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Checking for timing jump

 
Old 06-26-2011, 02:03 AM
  #16  
Charley B
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Well it looks like the driver side is off by about 7 teeth.
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Old 06-26-2011, 02:20 AM
  #17  
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Awww... I'm so sorry to hear this! Hope you can get it fixed soon, and enjoy that beast again.
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Old 06-26-2011, 08:26 AM
  #18  
Leon Speed
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Yikes! Hopefully the damage is not to much.

How much tension on the belt?
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Old 06-26-2011, 11:11 AM
  #19  
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Charley--

Maybe GB and the other more serious engine gurus will jump in on this. My amateur knowledge has me wondering how the heck that cam jumped that much and nothing else seems to be disturbed. It would take some serious available travel in the tensioner to let the belt ride up for that many teeth on the cam gear. It would seem to me that the slack from that would cause the belt to jump the passenger-side cam first. Per chance, did you check the belt tension as it sits now? That loose, at least on mine, would have the dash warning lit up well before there was that much travel in the tensioner.

Just my rambling thoughts...
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Old 06-26-2011, 11:44 AM
  #20  
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check the tension before removing the belt,
this isnt normal so something has failed for the belt to jump.
usually the teeth will, come off the belt.
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Old 06-26-2011, 03:28 PM
  #21  
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The tension is definitely on the light side but I don't have the experience to interpret degree vs impact.

There are no belt shavings anywhere but there is some damage to the leading edge of the belt here and there. Again, I don't know if it's enough to account for anything. I imagine the belt damage is the result of a worn cam gear or two.
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Old 06-26-2011, 03:39 PM
  #22  
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something broke off the belt run or fell into the belt run and damaged the belt the tension is way loose.

i would be checking the tensioner roller pivot bushings and the waterpump,
also remove the left cam gear bolt after fitting 3 small bolts to the rotor holes so the pulley wont turn on the cam / spider,
You would be looking for a snapped left cam snout.
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Old 06-26-2011, 03:47 PM
  #23  
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Stan, when you say left side are you referring to the passenger side or driver side?
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Old 06-26-2011, 03:58 PM
  #24  
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left side is the left side of the car or the driver side.

NOTE the cam that usually has a broken snout is the driver side cam, once the bolt is removed then the cam snout falls off if its broken or you will find that the bolt that holds the cam pulley on is bent
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Old 06-26-2011, 03:59 PM
  #25  
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Originally Posted by Mrmerlin View Post
also remove the left cam gear bolt after fitting 3 small bolts to the rotor holes so the pulley wont turn on the cam / spider,
You would be looking for a snapped left cam snout.
Been thinking this aswell, but wouldn't a snapped cam allow the gear to stay in place with the belt?
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Old 06-26-2011, 05:28 PM
  #26  
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Ouchh, 7 teeth off seems a lot to me.

Once had an alfa V6 that skipped 5 or 6 teeth, and practically all valves in that head were busted.

Hope you have more luck. Fortunately the belt did not break and (possible) damage seems limited to one head only.

Really curious to find out the cause of this problem.

Cheers
Michel
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Old 06-26-2011, 06:46 PM
  #27  
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Yikes, Charley! Did you get a low tension warning? I guess we have more to do on Wednesday than I thought. I will bring more tools. I have a new belt and other parts for a timing belt job which we will have to do before attempting a leakdown.
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Old 06-26-2011, 07:34 PM
  #28  
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Never got a belt warning. I should have all the tools we need, Bill. Unless you have a reason for me to leave the pully's and belt at this stage, for anything you might want to check, I'll go ahead and finish the tear down.
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Old 06-26-2011, 09:27 PM
  #29  
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just make sure the crank is at 45 BTDC before you try to turn the cams or remove the belt,
be on the lookout for an errant piece inside the belt run or at the bottom of the center timing cover,
for the belt to have gotten this loose another part would have to have failed.
Could be either
a damaged tensioner roller
or a failed WP bearing
or a broken cam on the left head( driver side)
or some other part that fell down into the belt run.
Sorry to see this Charlie
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Old 06-26-2011, 09:36 PM
  #30  
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Thanks Stan. Do I just move the crank to 45' or do I turn it 360' first and then to 45'?
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