Yellow Head Bolts
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Drifting
Joined: Nov 2003
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From: London, UK
Yellow Head Bolts
Porsche as of MY 1988 used galvanized and yellow passivated bolts for improvement in the friction between the threads and the aluminum / silicium these Yellow gold bolts replace the previous black phosphatzed bolts . They must be changed in complete sets.
NEW: Actually when I got back to the car some weeks later I found they were all yellow, I just got confused!
What should I do now? Budget doesn't really allow for a fresh set of head gaskets.
Last edited by UKKid35; Feb 17, 2004 at 09:04 AM.
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From: Southern NH
Hi Paul,
If you haven't done the final torque setting, I would think you could replace each bolt in question one at a time and torque each new one to the first stage after you install it. DON'T change them all at once. Your only at the first stage, so a one at a time change should allow the other bolts to keep the head clamped enough. I would then recheck all the bolts to the first stage torque before proceeding. Of course this is IMHO. Give some others a chance to share their thoughts on this.
If you haven't done the final torque setting, I would think you could replace each bolt in question one at a time and torque each new one to the first stage after you install it. DON'T change them all at once. Your only at the first stage, so a one at a time change should allow the other bolts to keep the head clamped enough. I would then recheck all the bolts to the first stage torque before proceeding. Of course this is IMHO. Give some others a chance to share their thoughts on this.
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From: Sydney AUS
Hi Paul
I am not certain that Jim Bailey was talking about 32V Head bolts - the rest of his quote goes on to talk 1983 and then changing the nuts in 1984. The head bolts on my '88SE - Definitely '88MY has black bolts. From memory they are Grade 8.8 bolts - nothing special about them at all unless you buy them from Porsche !
Regards
Jon
I am not certain that Jim Bailey was talking about 32V Head bolts - the rest of his quote goes on to talk 1983 and then changing the nuts in 1984. The head bolts on my '88SE - Definitely '88MY has black bolts. From memory they are Grade 8.8 bolts - nothing special about them at all unless you buy them from Porsche !
Regards
Jon
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From: Anaheim California
only the 32 valve engines (specificaly after 1986) have head BOLTS all earlier engines used studs . The recommendation to change all the bolts comes from Porsche to get uniform torque on all the bolts . I am quite sure there are a number of engines running about with mixed bolts and with a stock engine . My guess is it is O K ....desirable correct optimal NOPE . Since this thread involves some very ambitious horsepower goals , I thought it best to mention what Porsche recommends .
