ok, maybe i am using the wrong term for you folks on the other side of the pond
dipstick over here means the thing you pull out to determine if the crankcase has enough oil
you know "low.... full"
i am not talking about the dipper attached to some engines on the conrod lower cap.
having never seen an original 1930 lister, how do you check the oil level?
how do you know whether there is sufficient oil in the crankcase?
believe me i am painfully aware of the wholly inadequate big end oiling scheme used by the lister engineers
with the top holes in the upper rod brg area and the grooved upper brg.
yes i know it works, but i would have fired the engineer that suggested its use to start with.
that design sorely limits the power density of the engine, likely good enough for 3/1 and 5/1, and maybe 6/1 if all is
very good,, but over that and there are issues as evidenced by lister going to various other means of getting oil up there
with dipper, hollow dippers etc.
anyway, my question still stands,
how do you know you have sufficient oil in the engine? and are you sure it is adequate?
i would sure check to make sure, for obvious reasons.
as i previously alluded to, it is the oil splash up under the piston that cools the piston, you need to make sure you
have adequate oil getting up there.
i find it hard to believe that the engine reportedly runs fine, doesn't smoke unduely, which would indicate that
there is no real serious issue with fueling causing excess heat, that if there is enough oil getting up there it could not keep the
piston cool enough not to coke up the underside of the piston top.
bob g