JAP 2A Cylinder head gasket

On removing the cylinder head from my JAP2A engine, instead of a conventional gasket there is what appears to be a solid aluminium spacer about 1mm thick. Is this correct or is this a bodge at sometime because no proper gasket was obtainable?

That's the correct item as fitted at the factory.

Pete.

Many thanks for that.  I have come across solid copper gaskets before but not aluminium.  I have a modern replacement fibre gasket, would you recommend using that or re-using the aluminium, which shows no sign of having been blowing?

Also what about a plug?  The spec is L10, which is obsolete but I think can still be obtained from Green Plug (I use L10s in my Ford Model Y).  When purchased the engine was fitted with a Bosch Super RG271 which is a long reach plug unlike the L10 which is short.

I reuse the alluminium spacers but a smear of Hylomar etc on them helps to seal them. There were two different types of heads used on the 2a/2S's and one has a deeper thread on the spark plug location. I THINK (but not certain) that the deeper thread was possibly a modification to shield the plug to stop it fouling up, (Wolseley WD2's are similar) a short reach plug should still be fine but many folk do fit a longer reach one and as long as it clears the piston should work OK.

Pete.

Pete, Once more many thanks for your interest and advice. I now await the return of the magneto from Ribblesdale Electrics and then will be the big test to see if it works,

Regards

Richard

Be as well to re anneal the head gasket before fitting. Rub some block soap on it then warm it up with a propane torch until the soap turns black. Then leave to cool, this will soften it and let it bed in again.

As Pete says but I have seen cases where to long of a plug will clear the valves and piston but carbon up and make it difficult to unscrew and sometimes damage the thread in the head on the way out