Just on the offchance anyone is left here reading: my old boss's son acquired a bonser 3 wheel market garden truck from laying 10 years under a hedge.
All seems pretty clean, rings and bore good, spark is weak but low compression caused by rusting around the exhaust valve. He ( 12 years old) has started grinding the valve but the stem has now bottomed out on the tappet and cam. Does he have to renew the valve seat or can he shorten the valve stem?
AJH
Gosh there are still kids who like to get their hands dirty and make things work. Wow... B-)
Is there not an adjuster for the tappet clearance somewhere?
I don't know, I imagine the tappet is adjustable with a locking nut but as the seat is worn it has bottomed out.
AJH
In lieu of mechanical adjustment, carefully, squarely, and finely, grind the stem to achieve correct clearance.
Regards, DJC
I see what you are saying, bit difficult to grind in a valve without striping the tappet/rocker/springs etc. So presumably it's on reassembly that there isn't enough clearance. TBH that surprises me as all the adjusters I have seen (which isn't many) have about 1/4" to play with...
If the valve has had to be ground that much the seat and the valve really does need to be replaced. B-)
In lieu of mechanical adjustment, carefully, squarely, and finely, grind the stem to achieve correct clearance.
Regards, DJC
As per Ford sidevalve engines. I would be far from surprised if an industrial sidevalve engine did not use the same method.
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