godden cyl head seat failure

[perry graham fly]

i lost an exhaust valve seat (without disaster) on my twin. the heads came from godden and were re-heat treated before instalation. i have heard that this is a problem with them. anybody know the alloy they were cast from? how about seat interference info? any recommended solutions? perry graham fly

 

[timetraveller]

I do not know the alloy but this is now the third one I have heard of (see my comments in the Kent and Sussex Section in MPH a few months ago) so clearly they have a problem. My guess is that the interference fit is wrong. It should be five thou if the correct materials are being used. As there are alternatives perhaps the VOC Spares Co needs to have a word and look at alternative suppliers if Goddens cannot get it right. It is too much of a pain in the posterior problem to be endured.