SB-#978
August 30, 1963
SUBJECT: LOSS OF R.P.M. - 3 H.P. ENGINES.
Reports indicate that a loss of R.P.M. seemingly due to lack of fuel
has been experienced on 3 H.P. engines. Occasionally, the condition
has been severe enough to require the use of the choke to continue
running. Usually this problem is associated with contaminated fuel
or a restricted filter, however, recently some of these problems have
been traced to the apparent affect of fuels or their additives on
carburetor gaskets.
The additives in fuel affect each gasket differently. The float
bowl gasket swells which can restrict the fuel passages. The
nozzle gasket may disintegrate into small particles that can lodge
on the seat of the high speed needle or restrict the high speed
nozzle.
We therefore suggest that if you encounter an engine with an R.P.M.
loss, follow the usual procedure of inspecting the fuel filter lines
and tank. In addition, the carburetor bowl should be removed,
inspected, and reassembled using new gaskets.
JOHNSON MOTORS
Robert Compton
Administrative Assistant
RC:eb
NOTE: Post on your JW - 3 H.P. Index.