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90 GT No spark (thanks Rog, I was wishing)

 
Old 10-16-2008, 05:08 PM
  #46  
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Damn, that was just about the worst possile outcome. Easy for me to say, I know, but maybe just walk away from it a few days and regroup. It's worth more complete than in pieces. Sorry for the misfortune, Doc.
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Old 10-16-2008, 05:25 PM
  #47  
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OK so how do the cams stop turning, If the blet looks good at the cams then the teeth are sheared off at the crank drive.. This is a weird one, who built the front of the motor, were all new parts used?
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Old 10-16-2008, 05:28 PM
  #48  
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Just been to take a closer look and there are plenty of rubber shavings below the crank gear.
Belt has stripped at the crank.
Doc please tell me it was a new belt that you used????
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Old 10-16-2008, 05:45 PM
  #49  
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Hate to speculate, but is the oil pump turning?
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Old 10-16-2008, 06:02 PM
  #50  
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The oil pressure gauge was pegged so it should be replaced, otherwise don't know about the oil pump.

The belt is not moving at all, it's sheared off at the crank. The cams appear to be sitting about a 1/4 turn from TDC. Not tearing in to it today, going to let doc sleep on it and decide what to do in the morning. He's a bit upset, as I would be too.

If it were mine, I'd tear the front off and reset crank and gears. Put on a new TB and do a compression test to see if any valves were tapped. There are, and have not been any odd noises mechanically when the crank is turned. Hoping we got lucky.
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Old 10-16-2008, 06:08 PM
  #51  
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teeth broken, stripped of teef.
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Old 10-16-2008, 06:22 PM
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teeth broken, stripped of teef.
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Careful, Sean. Randy's going to be pissed if he hears you talking about his ex wife!

Very sorry to hear about Doc's motor. Here's hoping the victuals are intact.
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Old 10-16-2008, 06:30 PM
  #53  
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Sean--

Check the belt routing around the tensioner. There have bee a few documented instances whwre the belt was mis-routed there, allowing the belt to go tooth-to-tooth with itself as it passed over the rollers. That might explain why it stripped the teeth at the crank. maybe...

Doc, with all the effort you've put into getting it here, don't give up on it now. Market for 'interesting' cars is very very poor today, and selling one that isn't running is double tough at best. Find out what's going on before you do anything rash, like part it or give it away too cheap.

Stiff upper lip and all!
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Old 10-16-2008, 06:44 PM
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I was hanging out with Sean 2 days ago when he tried to start it. I did not hear any weird noises like pistons hitting valves when he cranked it over. I was at the front of the motor while Sean was cranking. It would kick over on I guess 2 cylinders and sputter and that's all she would do but no bad noises. Just sounded like it wasn't getting fuel/spark.

That's not to say that the damage was not already done before I got there, but there is a chance that no valves were damaged. Small, I know, but there is a chance.
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Old 10-16-2008, 06:49 PM
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Lack of noise means nothing ..... bending valves make little if any noise. Things get noisy when the heads of bent valves break off and get pounded between the head and piston.....I know that sound well in a 911 !
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Old 10-16-2008, 08:10 PM
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Here is the belt routing just before it was all put back together. Looks correct to me.
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Old 10-16-2008, 08:30 PM
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Doc,
Have few beers and cheer up. You are a great guy and a tremendous asset to the DFW group not to mention this board. Your technical skills are amazing and over the past few years I have learned much from you.
You have always helped out anyone in the DFW area when problems with there cars were beyond the norm. You always turn up to spin a wrench when ever needed.

Now its your turn for payback. Once we figure out what went wrong we can fix it like anything mechanical. I for one will give you as much of my time and as many of my parts that I can to get your car going. Your car can stay in my shop until she lives again - no argument. I am 100% that you will have a large group of local 928's putting up there hands to see "I want to help".

Maybe if we get a big enough group of wrenchs together we can rip out that aweful 5 speed and stick a real gearbox in there 8>)
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Old 10-16-2008, 08:33 PM
  #58  
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Originally Posted by SeanR View Post
Here is the belt routing just before it was all put back together. Looks correct to me.
Small observation Sean..................looks a little loose j/k how can we help?

In perspective; my wife just called to tell me my truck was stolen from a park and ride in Calgary................I just finished paying for the thing $60k..............now I'm drinkin'!!!!!!!!!

Last edited by the flyin' scotsman; 10-16-2008 at 08:54 PM.
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Old 10-16-2008, 08:44 PM
  #59  
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could one of the cams have seized in the head?? is it possible the headgasket was put on backwards?? that would block off oil... BUT the engine would have to have been running for the cam to seize, any way something else is stopping one of the cams from turning??? if you pull the front covers you can slide the belt off and turn the cams with a 30mm wrench..
Sorry to hear about this dilemma
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Old 10-16-2008, 08:49 PM
  #60  
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When installing the cams the bearing caps have a specific order. Once, I used bearing caps off another motor, torqued to spec and guess what? Cams were seized like they were welded there! This is a must check IMO.
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