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Checking for timing jump

 
Old 06-28-2011, 09:50 PM
  #61  
Stromius
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Great contribution there Charley. Just unbolt to redo the Hall sensor! That's a keeper.
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Old 06-28-2011, 10:50 PM
  #62  
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Originally Posted by Stromius View Post
Great contribution there Charley. Just unbolt to redo the Hall sensor! That's a keeper.
Yes, if you are doing a timing belt, removing the cam gear and spider and then the backing plate on that side is a trivial extra step and provides direct access to the Hall sensor. Otherwise it's a moderate PITA to replace the Hall sensor the "usual" way. I was remarking that the Hall sensor plug was so badly busted that we should replace it when Charley suggested we do it this way, and after looking at it for second I saw he was right. Hall sensor should be on the WYAIT list with a timing belt jobs.

Charley's 2-4% leakdown, as good as a fresh motor, was a very pleasing finding.

The belt had several paper thin slices cut off the front edge covering maybe 1/2 of belt length as well as a few gouges and cuts near the front for another 3rd of the belt length. Charley found evidence of something wedged between the belt and the inside of one cover near the front edge, but whatever it was, it was not in the area anymore. None of the teeth were sheared or showed any damage - the belt was a Porsche part. The water pump pulley was firm and spun with proper drag - water pump was a rebuilt Porsche with plastic impeller in perfect condition, although there was evidence of longterm weeping of coolant from the weep hole (bad seal - pump needs to be replaced). The tensioner arm bushings and pulley were in good shape. The tensioner had not backed off. The upper and lower idlers were free. The cam gears were in reusable condition and the spiders and cam noses were intact.
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Old 06-28-2011, 11:43 PM
  #63  
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I would be looking for something that fell or broke off of the timing cover and possibly is sitting at the bottom of the rear cover,if the belt has this damage something caused it though I dont understand how.
Its good that the compression numbers are spot on,
looks like you dodged a bullet
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Old 06-28-2011, 11:46 PM
  #64  
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Its a 928 miracle. You must be livin' right! Life is VERY fair today.
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Old 06-28-2011, 11:49 PM
  #65  
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Originally Posted by Mrmerlin View Post
I would be looking for something that fell or broke off of the timing cover and possibly is sitting at the bottom of the rear cover,if the belt has this damage something caused it though I dont understand how.
Its good that the compression numbers are spot on,
looks like you dodged a bullet
We checked around the bottom of the rear cover and couldn't find anything there or on the floor.

The bullet just missed.
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Old 06-29-2011, 01:29 AM
  #66  
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Very glad to hear this Charley! I just recently dodged a MAJOR bullet too, but mine was with a seized water pump. As I was reading through the thread waiting to hear the outcome, it didn't look good and I was starting to feel just a little guilty about my good fortune. Glad that you joined the Club (with a great assist from Bill)!!!
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Old 06-29-2011, 02:18 AM
  #67  
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Originally Posted by Mrmerlin View Post
I would be looking for something that fell or broke off of the timing cover and possibly is sitting at the bottom of the rear cover ...........................
Boy I know what you mean Stan. I have checked everything I could think of. A regular CIS investigation here. Bill even pulled the little pulley assembly under the crank gear in case something was hiding in the recesses there. No luck.

The only evidence of disturbance I could find was a spot in the center cover where the leading edge of the belt appears to have dug into a little hump in the plastic that rises to clear the power steering mount.
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Old 06-29-2011, 10:14 AM
  #68  
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that wear mark is from the belt being loose I was really hoping that you could find something. At this point I would strongly suggest to replace the water pump with a new Laso.
even though you have what seems to be a good pump if its been rebuilt then its suspect for the bearing migrating in the bore.
Period.
I have had to replace more than few rebuilds even though the bearing turned smooth and the precipitating factor was a belt warning with no other obvious indications on how the belt got loose.
In the long run, this step will save you lots of time from redoing this job. I promise!
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Old 06-29-2011, 02:04 PM
  #69  
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Why are you using "temp" flat head bolts on the spider? A normal person (no disrepect) would put the allen heads back in. (Disclosure: sometimes I am so **** I try to put the bolt or screw back in the threads it cam out of, whether it is being held there for storage or til the job is completed but that isn't really what is at issue here.) I'm trying to link that to a missing "X" that damaged the belt. You have not mentioned any damage to the cam gear. If something came loose and came between the gear and the belt allowing it to jump, wouldn't there be some evidence on the gear itself? Moving on, I'm glad for your good fortune.
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Old 06-29-2011, 02:28 PM
  #70  
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Charley--

Great news and you'll sleep more soundly now. All that clean living has finally paid off.
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Old 06-29-2011, 02:29 PM
  #71  
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Note the Allen heads in the rotors will be too long,
shorter temporary screws should be used to hold the cam pulley to the spider so the timing isnt lost though now with a new belt the timing should be reset putting the screws could keep the timing correct if it was already set
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Old 06-29-2011, 03:00 PM
  #72  
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Originally Posted by SteveG View Post
........................A normal person (no disrepect) would put the allen heads back in........................
Steve:

1) Awesome New York attitude, keep that.

2) I am not a normal person

3) Just because I am doing this job does not mean I know what I'm doing. I also put my chewing gum on the side of the fender before I started.

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Old 06-29-2011, 04:44 PM
  #73  
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Originally Posted by Charley B View Post
Steve:

1) Awesome New York attitude, keep that.
Stan noted a "normal" reason, thanks for the reminder. I have used Ken's gauge, but it's been so long I forgot that feature. Would indicate I should get it out and set mine again, perhaps.

I love a good mystery, but the ones on TV, always provide the solution at the end. We aren't going to get that here.

Glad to see you saw it the way I meant it. eceteraetcetera.
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Old 06-29-2011, 05:34 PM
  #74  
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Rock on Charley......sounds like all is well....

Have you started it up yet?
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Old 06-29-2011, 05:56 PM
  #75  
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Originally Posted by IcemanG17 View Post
.................Have you started it up yet?
Waiting for parts Brian. Gimmee a week or two.
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