which models had the cracked head problem?

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05-02-2007, 04:24 AM

#16

Larry928GTS

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I know of two that had a head crack. Both of them were '89 GTs.

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05-02-2007, 11:22 AM

#17

checkmate1996

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Quote:

Originally Posted by ACG

Sounds like he was here in Portland for the 2006 Porsche Parade.

That was it!

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05-02-2007, 11:26 AM

#18

Big Dave

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I had an '85 head crack...but in a different location. The chain tensioner mounting location broke off leaving only one lobe left for the tensioner. Yes, it sounded ugly.

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05-02-2007, 12:54 PM

#19

heinrich

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who was it? I was at the parade. There were 3 928's and I know them all .... all East-coast.

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05-02-2007, 12:57 PM

#20

checkmate1996

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Heinrich,

Ron Carr. At that time he was the local MORPCA president and 928 point of contact. He drives a silverish/blue 928...

Great guy. Extremely knowledgable...he's one of those mechanically minded types!

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05-02-2007, 03:54 PM

#21

Koenig928

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Quote:

Originally Posted by GregBBRD

The '87/'88 models suffered from the head cracking problem the most, although we've seen cracked heads in the '85/'86 models. The cracks occur in the radius where the head bolt washers sit, usually on the center two bolt holes. Very hard to see and very hard to figure out where the water is coming from....even with the heads off.
gb

Here's a picture to illustrate. This is the '87 head off the Koenig motor that was leaking coolant into the oil.

Much thanks again to you Greg for your advice during my rebuild.

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05-02-2007, 04:27 PM

#22

heinrich

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Bill that is interesting. Looks like a head bolt did that ... i wonder if it's a matter of torque spec?

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05-02-2007, 04:37 PM

#23

Raceboy

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This crack is really hard to find, especially when head is on the car!

And it sure looks to be caused by inequal or too high torque figure.

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05-02-2007, 04:45 PM

#24

Big Dave

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Quote:

Originally Posted by Raceboy

This crack is really hard to find, especially when head is on the car!

And it sure looks to be caused by inequal or too high torque figure.

I can only imagine all the time spent trying to track that down

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05-02-2007, 11:50 PM

#25

Koenig928

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Quote:

Originally Posted by heinrich

Bill that is interesting. Looks like a head bolt did that ... i wonder if it's a matter of torque spec?

I'm sure that played a part in it, given all the other things I found wrong on this engine.... Although I suspect the supercharger contributed as well with the heat dump you get while under boost. Even though it did take ~13 years for one the heads to crack....

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