Royal Enfield 500 TWIN 1949, Workshop Maintenance Manual

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ROYAL ENFIELD WORKSHOP MANUAL
The ports in the housing are connected as follows
W - delivery to rocker gear. Y - suction from oil tank.
X - delivery to big ends. Z - suction from oil tank.
Position 1. The plunger A is being drawn out of
the cylinder hole in the disc C by the action of the peg
B on the shaft D. The port T in the disc C registers
with the suction port Y in the housing, so that oil is
drawn into the cylinder from the oil tank. At the same
time the delivery port W in the housing is uncovered
and oil below the disc in the housing is forced through
W to the rocker gear.
Position 2. The plunger A is being pushed into the
cylinder hole in the disc C. The port T in the disc
now registers with the delivery port X in the housing,
so that oil is forced out of the cylinder to the big
ends. At the same time the suction port Z in the
housing is uncovered and oil is drawn into the
housing below the disc from the oil tank.
The ports in the housing are connected as follows :
W' - delivery to oil tank. Y' - suction from crankcase. (On early models Y'
X' - delivery to oil tank. Z' - suction from timing chest. and Z' were reversed)
Position 2. The plunger A' is being pushed into the
cylinder hole in the disc C'. The port T' in the disc
now registers with the delivery port X' in the housing,
so that oil is forced out of the cylinder back to the oil
tank. At the same time the suction port Z' in the
housing is uncovered and oil is drawn into the
housing below the disc from the timing chest.
Position 1. The plunger A' is being drawn out of
the cylinder hole in the disc C' by the action of the
peg B' on the shaft D'. The port T' in the disc C'
registers with the suction port Y' in the housing, so
that oil is drawn into the cylinder from the crankcase
sump. At the same time the delivery port W' in the
housing is uncovered and oil below the disc in the
housing is forced through W' back to the oil tank.
Section B1 Page 4
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