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The usual very well done and informative video from Tubs… thank you.
Just to elaborate on the last issue “too warn to fix” …. yes that can happen with these real small motors. In many cases that issue is low or no crankcase compression due to worn crankshaft bushings. Since there are no crankcase seals, crankcase sealing depends on the tightness of the crankshaft bushings. Low crankcase compression will cause hard or no starting and poor low speed running. Check for excessive back and forth movement of the flywheel, indicating worn bushings. A richer mix of heavy 40 W oil may help.
Can this problem be fixed? yes, if you have a machine shop or a friendly neighborhood machinist.
Joe B
In my experience its the loss of compression
that I haven’t been able to overcome. The
wear in this cylinder below has resulted in a
taper of .016.
After fitting a new ring at the bottom, by the
time it gets to the top of the cyl. the end gap
is large enough that the compression loss is
too much for a motor this small to overcome.
My attempt to add material to the top of the
cylinder to increase compression has been a
failure.
However Joe has a point.
When I first started messing with motors in
the 50’s, new rebuild parts weren’t as available
or cost effective as they are today.
After truing the cylinders the skirts on the
old pistons would be knurled and then turned
to fit the now oversized cylinders.
Along with oversized rings this produced a
pretty good result. Some claimed it was better
than new as the knurling carried extra oil.
A piston this small could be made out of a
chunk of a aluminum if one had the equipment
and a mind to.
A fixture could be made to hold the cylinder
so one could true it if one had the equipment
and a mind to.
No only could one be made to run again,
from some of the skills Mumbles and
the Buccaneer have demonstrated in their
postings I believe there are people right here
on this board that could make one run again –
if they had a mind to.
I have the mind to but lack the skills and
facilities.
Heavy oil and a lot of it is worth a try. It may
be just enough to get one to run depending
on its condition.
Tubs.
A "Boathouse Repair" is one thats done without having tools or the skills to do it properly.
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