copper head gasket

[PRG]

Howdy Eric,

Have had these in service for 30 years on a 440, 441, 346 and 348 and would not return to composite for any reason. As an aside, the huge torques spec’s for composites back in the day was to crush those gaskets into submission where they were most prone to failing, the high heat area around the exhaust valves. After 70-80 years of this stress, Four cylinder heads especially become distorted at the head bolt washer lands as to be unusable. With copper, I torque to only 30ft lbs, no glues, treatments or leaks. The key thing is surface prep, ie, all adjoining surfaces must be flat. You will note your gaskets have stamped out on sheet with a small lip around the underside from shear, the underside surface is not as smooth as the top side. This and the other surfaces can be addressed merely by dressing them on 600-800 grit paper on a sheet of glass.

Though not as prone to distortion, v twin heads can become deformed on the face at the washer lands especially around the exhaust pocket. In some cases, because of non OEM or stretched original head bolts, overzealous tightening results in bolts bottoming out and the cylinder threads stretching up profound of the deck. A pass or two with sand paper on glass will reveal those areas if present. Finally, the heat transfer rate between deck and heads is hugely aided by copper, especially if dressed as the more surface area in contact the more efficient that transfer is. Very important for this of us living down south and summertime urban riding.

[T. Cotten]

If you gotta seal them with paint, Folks,...

Then what's the point of the gasket?

Thanks in advance.

....Cotten
PS:

... Anneal them and I spray them with copper coat. They can be re used also if you anneal them before re use.

That makes me wonder, PanheadFred,...

What hardens them when used?

[PanheadFred1]

I've been using copper gaskets for a while now and I'm very pleased with them. Anneal them and I spray them with copper coat. They can be re used also if you anneal them before re use.

[RichO]

Rubone, I use the"Big" bottles of silver I get at the hobby shop for models.It's like the old ones you remember. Cotton, I have good success with copper ones on my WL with #5 aluminum heads but I don't know if they were used as OEM.

[T. Cotten]

Just curious Folks,...

Were OEM gaskets for aluminum heads copper, or composite?

Thanks in advance,

...Cotten

[Rubone]

Silver paint has always been the best, but modern paint does not have the aluminum content (the part that made the seal) like early ones did. Old high heat silver H-D paint had a high aluminum content and was available in cans, not just aerosol spray.

[RichO]

I anneal them then coat them with the dregs of silver paint after I drain off the clear that it's suspended in. But you can use copper coat too. It ( the paint method) always worked on my 101 but I'm sure you'll get other methods offered..

[exeric]

I got the thick copper head gaskets for my '41 Scout from Greer. I've never used gaskets like this so I would like to hear from those who've used them. Opinions, tips, tricks, love or hate would be most appreciated.