Oil Pump - Matchless 1949 CLUBMAN G3L Maintenance Manual And Instruction Book

12 CHECKING OIL CIRCULATION
Provision is made to observe the oil in circulation and it is necessary to do this before
each run.
If the filler cap on the oil tank is removed, the returning oil can be seen running from
the small spout just inside the filler cap orifice. This check should be made immediately
after starting the engine from cold. This is because while the engine is stationary, oil
from all parts of the interior of the engine drains, back into the crankcase sump, so that,
until this surplus is cleared, the return flow is very positive and continuous. Therefore,
if the oil circulation is deranged, the fact is apparent at once by the lack of a steady
return flow.
It should be remembered that normally the return flow is somewhat spasmodic and
mixed with air bubbles. This is partly due to the fact that the return portion of the
oil pump plunger has greater pumping capacity than that delivering fresh oil, and partly
due to the variations in the amount of oil in suspense in the crankcase according to the
engine speed. For example, upon a sudden acceleration, the return flow may completely
cease for a time, only, of course, upon deceleration, to resume at a greater rate than
normal.
13 PILLION PASSENGERS
The addition of weight to the rear of a motor cycle may affect its steering. Therefore
the rider must make some allowance for the difference in the "feel " of the machine
when a passenger is carried.
The rear tyre pressure must be increased to satisfactorily carry any increased load.
(See Para. 97).
Illustration 4
Showing the oil tank with the felt filter in
its cylindrical housing and the metal strainer
mounted on the entry end of the feed pipe
union. Also shows the direction of flow of
oil from tank to engine and return flow from
engine to tank via the small spout, located
so that it can be inspected by removing the
tank filler cap (mentioned in Para. 12).
12