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Collection, Preservation and Display of Old Lawn Mowers

Jap 2a

Hi guys I'm a new member, looking for bit of advice, I'm restoring a Jap 2a, was wondering how you adjust the taps for valve clearance, when you put the camwheel on it covers the valve stems and can't get at them with feeler gauge

markyboy Fri, 25/08/2017

Thanks wrist pin, I also have another manual on Jap engines and doesn't seem to mention on the rebuild part either! I'm think of just putting to TDC with cam in, then trying to remove again without disturbing the valve lifters, there very indented, don't know if it's just wear, but I think she's been past around abit and had a few bad restoration jobs, when removing the valves the inlet looked as if someone had just ground them in! Exhaust was opposite as if it was never touched! 

markyboy Fri, 25/08/2017

You wouldn't know who's best for spares for these little engines? I'm looking 2x crankshaft bearings and could shells for big end. Also have another two stroke on a Ransomes spirit probably need bits for, pics to follow for this

merryman Fri, 25/08/2017

I've no experience of the Jap 2a, and know there are exceptions like Briggs & Stratton's "easy spin," but most single cylinder engines are "off the cam" when both lobes point downwards like an upturned V, so if you put the cam in like this, then set clearances, they should be right. Usually the keyway is either at the top or bottom when they are at this point too.