"William Noble" wrote in message
.. .
the kerosene thing is mentioned in the service manual for my 1938
plymouth - as I recall, add, idle, drain, and refil with regular oil - no
longer practiced, we have detergents in oil.

I can imagine it would work on really old engines if you did it regularly
and just ran the engine lightly. My guess is that the problems crop up when
you use it to try to salvage an engine that's already full of crud, and you
run it too hard or long.

--
Ed Huntress