Copper Head Gaskets

[vanzen]

I think the torque to properly seat a copper gasket would be greater than that to seat the composite OEM gasket.

This thinking would be incorrect.
Torque specifications are determined by the fastener(s) being used
and not the material composition of a gasket.

Copper head gaskets are often considered to replace the stock item
in circumstances where compression ratios exceed stock specs
or as a means to (marginally) alter existing compression ratios.

[Jean]

vanzen, I wasn't considering challenging the fastener. The "bolts" (screws, since they go into tapped holes!) used on an airhead engine are capable of a lot of torque, but the threads in the block will fail first.
THAT was the only point of the comment.
I agree a copper gasket will perform better at higher pressures but only if the mating surfaces are properly prepared. They are more sensitive, IN MY EXPERIENCE, to surface imperfections.

[moonbeamerll]

Disambiguation:
http://en.wikipedia.org/wiki/Screw#Diff ... _and_screw

[Major Softie]

Disambiguation:
http://en.wikipedia.org/wiki/Screw#Diff ... _and_screw

Oh LOOK! MoonbeamerII is channeling Lonnie!

[vanzen]

vanzen, I wasn't considering challenging the fastener. The "bolts" (screws, since they go into tapped holes!) used on an airhead engine are capable of a lot of torque, but the threads in the block will fail first.
THAT was the only point of the comment.
I agree a copper gasket will perform better at higher pressures but only if the mating surfaces are properly prepared. They are more sensitive, IN MY EXPERIENCE, to surface imperfections.

All fasteners used by BMW are required to be torqued to specification.
This specification may be generic (dependent upon the characteristics of the fastener in question)
or application specific as determined by BMW.
"A lot of torque" will ALWAYS BE a certain specified value
as determined by either DIN (Deutsches Institut für Normung) or BMW.

Disregarding, and especially, exceeding applicable torque specifications
is a sure-fire way to weaken, distort, and ultimately "pull" the threads from any aluminum casting
whether those will be in the block for the cylinder studs (called "tierods" in the BMW manual)
or in the final drive for a screw plug.

I think the torque to properly seat a copper gasket would be greater than that to seat the composite OEM gasket.

Succinctly and without malice:
The torque to properly seat a copper gasket IS NO GREATER than that to seat the composite OEM gasket.
In fact, the torque to properly seat a copper gasket will be EXACTLY THE SAME
as that to seat the composite OEM gasket.

Furthermore, the function of torque is NOT to "seat gaskets".
even as it may be considered a consequence.
Proper applied torque is designed to guarantee the integrity and function of the fasteners involved.
Any attempt to resolve a leaking gasket with the application of "more torque" than is specified –
will be pure folly ... and likely result in the above "only point of the comment" !

Any successful gasket installation will depend upon proper prep and installation.
The prescribed use of a sealant with a copper head gasket
is intended to compensate for the imperfections of the freshly annealed copper surface
and ensure gasket, head, cylinder sealing.
The method works well.

... or am I missing the sarcasm again?

[Jean]

yep.
"Any successful gasket installation will depend upon proper prep and installation."

Haven't you heard "If it leaks, tighten it!"...?
I may have failed to mention I tried unsuccessfully for over 20 years to convince my mechanics at the powerhouse that a leaking flange gasket on a feedwater heater would NOT respond to just more tightening on the stud nuts.

They bitched a lot when they had to extract a broken stud...HOT.

[moonbeamerll]

Disambiguation:
http://en.wikipedia.org/wiki/Screw#Diff ... _and_screw

Oh LOOK! MoonbeamerII is channeling Lonnie!

I just hate to miss an occasion to use the word "disambiguation"! It is so rarely used and so often needed.

[Major Softie]

Disambiguation:
http://en.wikipedia.org/wiki/Screw#Diff ... _and_screw

Oh LOOK! MoonbeamerII is channeling Lonnie!

I just hate to miss an occasion to use the word "disambiguation"! It is so rarely used and so often needed.

It is the bolt vs. screw part that was a pet peeve of Lonnie's.

[John Falconer]

1) Anneal the copper gaskets, you can quench them - no problem - did it for years with Triumphs, etc.
2) Use the special copper-gasket-specific gasket sealer if you can get it (people who sell such gaskets sell this also)
3) Be prepared, in spite of all you care and efforts, for some leakage.

John

[Nourish]

I was just about to go out and buy a can of HYLOMAR UNIVERSAL 'M' AEROSOL GASKET SEALANT but took a minute to look up the spec and it's operating range only goes up to 250c - That's not high enough is it?