928mac

I think most manufactures say to replace the bolts every time but I thought that I would ask what is normal with you guys.

Are new head bolts required every time you do head gaskets?

blown 87

I replace any head bolt that is a torque to yield bolt, which is almost always one that has a torque plus degrees.
so yes, I replace 928 head bolts, with only Porsche bolts, no aftermarket "super, better" bolts, cause they are neither super or better.

Rob Edwards

Yes, replace 'em.

928mac

Roger ! yooo hoooo

Looks like I will need all new head bolts and might as well send cam cap bolts as well

BTW thanks Greg and Rob

Rob Edwards

2 things:

2 different lengths of head bolts, 19 mm longer after engine # 81K 05328. You have an '89, make sure you order the right length bolts. (in fact, it would be interesting to list your car's date of manufacture, engine serial #, and whether they're R1 or R2 heads....)


Be careful before signing off on new cam cap bolts, there are 52 (54?) of them and they're $7 or $8 per, IIRC. They're safely reused as long as the heads aren't stripped or rounded.

blown 87

They could be R3 heads, that is what came off my 89.

AO

There was a really good thread on this about a year or so ago. Greg Brown measured the torque that results from the 3 90° tightening sequence. And as long as the re-used bolt results in the anticipated torque, you should be good. Obviously if it doesn't, you need a new bolt.

GregBBRD

Porsche does not insist that the head bolts get replaced after every use...like they do on the rod nuts.

I replace the bolts with fresh bolts on every rebuild/valve job. I am not afraid to torque them and loosen them, if the bolts are new. I believe that they stretch, but are not yielded.

928mac

They are sir #928 104 413 3R heads 1 short bolt frt driver and 1 short rear pass
block is a M28/42 81K 07629
Japan vin#WPOZZZ92ZKS842476

$7 e for those cam cap bolts, . . you got to be kidding me, thats 378 bucks

Rob Edwards

Honestly they may be only $4 per, but that's still way too much for reusable bolts.

928mac

Thanks for the heads up Rob.

I have already sent Roger the e-mail and he will let me know.

BTW when the double square strips out I discovered that a #tx 45a Torx socket will tap in and take them out

GregBBRD

If you give them a good solid hit with a brass drift and use a Hazet socket to remove them, you will not round them out. I've rounded off dozens of Snap-on tools, made for this, over the years. I used to start with one new tool and switch it out, halfway through with a second tool. I'd then give both to my Snap-on dealer and he would replace the "bits". I probably have a half a dozen of these things, in my box.

I finally gave up and only use the Hazet tool. I've used the same one for years and have never worn it out.

blown 87

Greg Brown has a sign about that.

AO

"Pay up sucker!" ?

Brent

Now that's some info I can really use. Thanks Greg.