Solid aluminium head gasket

Rebuilding my JAP 4/2 engine I had a replacement head gasket arrive today. I was surprised to see a solid aluminium one?
Parts diagram I have looks like it could well be a solid one but I was expecting the more usual pressed assembly.
Upon original dismantling I found no gasket just red sealant!
Do you think I ought to add a sealant to the solid one on assembly?

Alan

Yes a lot of the JAP engines used a solid alloy gasket. I usually smear a light film of Hylomar on either side and that seals them, I have had a couple leak compression otherwise.

Pete.

Thanks Pete, would that be Blue Hylomar? (because I have some!)

Alan

Alanengine wrote:Thanks Pete, would that be Blue Hylomar? (because I have some!)

Alan

Yes mate.

Pete.

Cheers!

Alan

Jap engines had a love affair with solid alloy gaskets. They can be hard to seal as many are now many years old and age/work harden. I always anneal the gaskets before fitting. An aluminium gasket can be annealed by first rubbing a bar of soap on it. Then gently heat evenly with a blow lamp until the soap turns black, then leave to cool. it should then be fine to fit.
Just as an aside what year is your 4/2. I have a very early one at 1935 with a 3 part air cowl and cast iron engine construction.

I did wonder about the hardness of the alloy, I will anneal it before use just to make sure.
Mine is from 1940 with a 2 part cowling and like yours is all cast iron, consequently quite a lump!
Been impressed with it's construction and although it only ran for a few seconds before purchase it sounded really good with a nice exhaust note.
I've found the base colour of the engine as black but have also found green on the inlet/exhaust manifold, what colour is yours?

Alan

On my engine the original colour of the engine crankcase and sump was black gloss with black also on the cylinder and an unpainted head. The air cowling, inlet manifold and fuel tank where of dark green. I painted the whole engine grey but as I was only 10 at the time {and an now 52} I think I will repaint it to the original colour. It was the first engine I ever bought and have never parted with it.
Hope this helps.

Regards

Dale.

Thanks, I've been finding black on the engine and no paint on the head. Trac s of green were on the manifold but as for the cowling and fuel tank I don't think I have found any paint!
Was your cowling also green with the tank?

Alan

Tank, air cowling all three parts, and manifold was dark green. Not unlike British steel furniture green that they used to paint filling cabinets. BS 279.

Dale.