Matchless 1964 G12 650, Instruction Book, Page: 15 / 104

CHECKIN G OIL CIRCULATION—ALL MODELS
Provision is made to observe the oil in circulation and it is advisable to do this before
each run.
if the filler cap on the oil tank is removed the end of the oil return pipe will be noticed
below the level of the filler cap orifice and the returning oil can be seen running from
it. 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.
1
2
3
OUTLET IN OIL RETURN PIPE.
LEVEL INDICATOR LINE.
OIL RETURN PIPE.
4
5
6
OIL FEED PIPE.
OIL FEED GAUZE FILTER.
DRAIN PLUG.
7 VENT PIPE.
Interior view of the oil tank showing the metal strainer mounted on the entry end of
the feed pipe union, the return flow pipe from the engine to tank via the small spout,
located so that it can be inspected by removing the tank filler cap, and air vent pipe,
provided to ensure freedom from air-locks.
After removing oil pipes verify location before refitting. W i t h exception of
CSR Models the return pipe is outside, before 1963 Models.
E N G I N E L UBRI CAT I O N SYSTEM—SINGLES
This is by dry sump system. Oil feeds, by gravity, from the oil tank to the pump In the
crankcase. The pump forces oil to various parts, which then drains to the bottom of
crankcase sump. The pump then returns oil to the tank. This process is continuous
while the engine is revolving. The pump is
so
designed that it has a greater capacity
on the return side to that on the delivery side to ensure that all oil is extracted from
the crankcase. A magnetic filter in the sump removes foreign matter collected by
the oil in its passage through the engine. A metal gauze strainer is fitted to the oil
feed pipe in the oil tank to prevent pieces of fluff, etc., which may find their way into
the tank when replenishing, from entering the oil pump. (See illustration 3.) It should
be cleaned in petrol each time the oil tank is drained.
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Illustration 3
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