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Engine coming out for Head Gaskets and WYAIT's - UPDATE: Heads back on!

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Old 05-22-2012, 12:49 AM
  #91  
Imo000
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The solution is to get some sealant on that spot, reinstall the gasket and enjoy the car.

I don't think a paper gasket material can indent the aluminium, the head was slightly dropped on something hard before assembly (either at the factory or when you had it apart).
Old 05-22-2012, 03:18 AM
  #92  
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Originally Posted by Imo000
The solution is to get some sealant on that spot, reinstall the gasket and enjoy the car.

I don't think a paper gasket material can indent the aluminium, the head was slightly dropped on something hard before assembly (either at the factory or when you had it apart).
That was my first thought, but that doesn't explain the corresponding dents in the head and in the cam tower mentioned in post #84.

The matching depressions seem to indicate a common source - something where it shouldn't be.

Whether a paper chad could do that? I don't know.

For me, I would do as you suggest - add some sealant at that spot, assemble, and go driving.
Old 05-22-2012, 07:20 AM
  #93  
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I don't know what the torque spec is but how could a paper chad dimple an aluminum casting? Your theory of the bolt pushing the chad aside doesn't make sense to me unless the factory installed the gasket on the cam tower first, inserted bolts and them flipped the whole assembly on to the head. Why fight gravity?

So what's your plan to stop the leak?
Old 06-10-2012, 02:46 PM
  #94  
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Default UPDATE: No Leaks, but....

The car is all together and running great, with no leaks! We are chasing down one last issue: the clutch.

On stands and on a short drive around the neighboorhood, the clutch worked well - about the same as before. After cool down, and re-start, we are not getting full release of the clutch - grinding when selecting any gear at rest.

During this whole exercise, we replaced the clutch master/blue hose, release bearing, ball cup bushing, and greased everything up properly. We have adjusted the IP, and properly bled the system. Now suspecting the MC piston stop length. We didn't compare the length old to new (I know, should have), but measured the old one today, which is 80mm. What should the piston length be for proper clutch release? I seem to see reference of about 75mm after trimming. We are getting ~ 17mm travel at the slave - which I think should be enough.

It should be noted that I had issues with the clutch dragging before with the old MC. I suppose it is possible that the PO had replaced the MC before, and the piston length in the replacement was too long (the 80mm we are seeing in the one we replaced).

Thoughts on what the overall length of the piston should be? Thanks.
Old 06-10-2012, 02:49 PM
  #95  
Speedtoys
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Originally Posted by tilac999
I don't know what the torque spec is but how could a paper chad dimple an aluminum casting? Your theory of the bolt pushing the chad aside doesn't make sense to me unless the factory installed the gasket on the cam tower first, inserted bolts and them flipped the whole assembly on to the head. Why fight gravity?

So what's your plan to stop the leak?

Pressure + time + soft metal.


EZ.

A human hair will imprint steel in a mill too.
Old 06-11-2012, 12:06 PM
  #96  
tilac999
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Bummer about the clutch. Hope you can get it sorted. Give a call if you need some help. Good luck.
Old 06-17-2012, 10:56 PM
  #97  
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It was a great Father's day, as I was able to attend the German Car Day lawn event at the Larz Anderson Auto Museum in Brookline MA today in the 928. I took a spirited back road drive early in the AM with some other German car guys, and the 928 performed flawlessly. Then my wife and 2 daughters met me at the show and we had a nice picnic lunch. My kind of day.

We finished up the clutch master mod Friday, and I drove it home Friday night. First night in my garage since Feb.

This has been an interesting experience, and there isn't much I fear now on the car. Yes, there are still things beyong my wrenching capabilities, but my levels of confidence and understanding are much higher than I would have ever imagined possible.

While I did a lot of the wrench turning, Dave Chamberland did the heavy lifting, and kept me on track and out of trouble. I can't thank him enough for sticking with me as one surprise after another kept resetting the schedule.

Thanks to those who followed and helped with ideas, suggestions, comments, and encouragement - all of it was helpful and appreciated.
Old 06-18-2012, 07:03 AM
  #98  
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Excellent and good to hear.
Old 06-18-2012, 07:20 AM
  #99  
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That's what it's all about! ...When it all comes together.

I like that feeling of confidence you described. Knowledge is power. In this case, Horsepower!



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