Anyone know where I can get a manual for a howard gem? I see that Internal fire list quite a few manuals for JAP engines but I don't know which model it is? What is the correct way to anneal a copper head gasket? lastly any web links for JAP enthusiast's? thanks, Kev
Howard gem questions
Apr 12, 2005
2 Replies
It's going to be one of the larger engines like the 500cc or 600cc for the rotovator.
Look on Google for "Howard Gem Rotovator" I found a few links for books etc.
If the gasket is solid copper then heat to almost red hot and drop edgewise into cold water.
If copper asbestos then heat and let cool slowly.
Peter
I often use oxy acetylene for this, but you do need to keep the torch moving A propane blowlamp is plenty hot enough.
In theory as Peter said you should quench from dull red for maximum effect, but in practice I doubt that you would notice the difference whether you do or don't quench.
Cheers Tim
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