Crushed Copper shims!?

[hbrand]

When disassembling my engine, I found the copper shims crushed and squized out at the bottom of the cylinders.

What can I replace those soft copper shims with??

One more please:

Are this Mahle or JE pistons?

[tab tanner]

Those are copper base gaskets I think the host sells them. There not very expensive. The piston look like a Mahle to me I may be wrong? But I don't think so? Get Wanyes book: How to rebuild and mod your 911 engine, All your questions will be answered

[tab tanner]

I just saw that you bought the book! Good going

[Wayne 962]

Offhand, they look like a typical Mahle cylinder, but I'd need more pics of the inside, etc to tell...

-Wayne

[hbrand]

Hello wayne
will post more piston pictures tomorro.
because of the crushed and slipped out cooper shims, the cylinders leaked at the cylinder head. So I gues i can only use the most thick once I can buy.

Can I post all the parts I need to order here and you give my the part numbers, or can your sales people handle zb ring set 92mm, 1.5x1.5x3mm, turbo cylinder head gaskets for 2.7 turbo

thanks, harold

[kstylianos]

Harold,

I wouldnt 'use the most thick once I can buy' as shim thickness needs to be selected to bring your deck heights to spec (you'll find this info in the book). The shims you posted are not typical....they appear to have been reused, installed incorrectly or the head studs possibly over torqued. In any case, not typical. You should be fine using the the correct thickness coppper shims, making sure your case and cylinder bases are flush and keeping the head studs torqued to spec.

BTW: Pistons do not apperar to be JE.

[Jeff Alton]

Them there look like Mahle's. not JE.

[Wayne 962]

Originally posted by hbrand
Can I post all the parts I need to order here and you give my the part numbers, or can your sales people handle zb ring set 92mm, 1.5x1.5x3mm, turbo cylinder head gaskets for 2.7 turbo

There is no such thing as a 2.7 turbo. Is this that engine that you bought on eBay? Did you bolt a Turbo on it? With single plug and 11.5:1 compression? If yes, then it's no wonder the thing fell apart. Now I'm really confused.

Those cylinder base gaskets don't just get like that. This engine was beat to hell, potentially from detonation? Then perhaps the head studs pulled and the cylinders got loose and banged around the copper base gaskets. You just don't see that when tearing down an engine, unless the whole thing was imploding...

-Wayne

[hbrand]

I hate turbo engines.
My thought was if the head is leaking I can work on the surefaces and install some kind of head gaskets. some members said the turbos had them - but that would be 3.o ltr and they would not work on my 2.8 ltr
I do not know how this engine was run by its former owner, all I want this engine to be is a fast long lasting stret engine.
thanks, harold

[cstreit]

WHat's with the cast looking surface on those pistons though, haven't seen that before on a Mahle piston.

[hbrand]

More piston pictures. Mahle or J E??

[Wayne 962]

Originally posted by hbrand
I hate turbo engines.
My thought was if the head is leaking I can work on the surefaces and install some kind of head gaskets. some members said the turbos had them - but that would be 3.o ltr and they would not work on my 2.8 ltr
I do not know how this engine was run by its former owner, all I want this engine to be is a fast long lasting stret engine.
thanks, harold

If this was the other motor you're talking about, it's not ever going to be a long-lasting engine, if you keep it in this config. 11.5:1 - nothing long-lasting about that, particularly with a magnesium case.

Take a look again at some of the chapters in the book, and that should help you decide what to do.

These pistons look forged to me - they look very much like Mahle RSR style pistons. They don't look like any JE pistons I've ever seen. The JE pistons I've seen are all machined across the top of the cylinder. These tops (minus the pockets) were forged.

-Wayne

[hbrand]

Thanks wayne, first will determine the compression ratio I have and the zero in for about 10.

Will post nice pictures soon.

Thanks, harold

[Wayne 962]

Originally posted by hbrand
Thanks wayne, first will determine the compression ratio I have and the zero in for about 10.

Will post nice pictures soon.

Thanks, harold

If this is that 2.7 engine, I would assume nothing and measure everything...

-Wayne

[snowman]

Something banged the hell out of these copper spacers. Nothing std or within spec could cause this type of damage. And it is DAMAGE, big time. Do not put this thing back togather without finding out exactly what caused this.

[rcwaldo]

Looks like 'fretting' caused by loose cylinders (pulled headstuds or undertorqued head nuts).

[snowman]

rcwaldo stated the most likely cause.

Question- could this also be caused by pre ignition? In other words head studs pulled or stretched due to extreem pressure generated by pre ignition due to high compression ratio. See Waynes comments above.

In any case I would use only copper shims on rebuild. Thick copper shims are available if needed.

Long lasting street engine? CR on a Porsche is effectively about 1 point higher than on a water cooled engine according to Bruce Andersons book. Using premium gas with an ignition that includes knock detection would seem to limit the CR to 9.8:1. Otherwise without the knock detector to maybe 9.3 to one max. Thats for long lasting.

Your case almost certainly needs to be re decked as well.