Oil Circuit; General Description - Triumph Rocket III Service Manual

Lubrication
Oil Circuit
General Description
The Rocket III utilises a dry sump iubrication system
whereby a pressure pump takes oil from an oil tank
and delivers oil under pressure to the engine and
transmission. A scavenge pump coliects oil from the
sump and returns it to the oil tank.
The oil tank is attached to the upper crankcase on the
ieft hand side of the motorcycle. Situated within the
lower crankcase, the pressure pump is gravity fed
from the oil tank via an internal drilling. An oil tank
drain plug is situated at the lowest point in the drilling,
in the sump itself.
Scavenge System
Pickups from the double-ended scavenge pump
coliect oil from the front and rear of the sump and
return it to the oil tank. Further drain plugs are fitted to
the front and rear of the sump to drain residual oil
from the sump.
Pressure System
From the pressure pump, the oil is delivered along an
internal passage, past the oil pressure relief valve.
The oil pressure relief valve relieves excess oil
pressure by aliowing oil to return to the sump. Once
past the oil pressure relief valve, the pressurised oil
goes through a one-way valve whose purpose is to
prevent the oil in the tank from draining into the lower
crankcase area.
From the one-way valve, the oil is passed through the
oil filter. Filtered oil is fed directly to the main oil
gallery for distribution. Drillings from the main oil
galiery feed oil to the four crankshaft main bearings.
There are also three piston oil jets, located in the main
bearing housings which lubricate and cool the
pistons.
Oil is also fed from the main oil gallery, through
internal drillings and pipes, to the transmission. The
transmission input shaft is both drilled through its
entire length and cross-drilled. The cross drillings
provide oil directly to the gears, selector forks and
bearings. Oil flowing through the centre of the shaft
exits at the clutch end, to provide oil to the clutch
assembly. A spray jet for the outside of the clutch is
mounted directly to the pressure pump. The torsional
damper shaft is also fed from the input shaft. The
torsional damper shaft is cross-drilled to feed the
gears, bushes and other running surfaces. An
internal passageway carries oil to the output shaft
bearing and then on to the output shaft. The output
shaft is also cross-drilled to carry oil to the gears,
selector forks and bearings.
The cylinder head is fed via an internal driliing coming
from number 4 main bearing. Within the cylinder
head, a passageway through the cam ladder feeds oil
to the camshaft bearings, and spills oil onto the tappet
buckets and the valves. Spill oil returns via the cam
chain area to the sump, lubricating the cam chain in
the process. Also located off the cylinder head supply
is an oii jet which cools the alternator. The low oil
pressure warning switch is located at the rear of the
cylinder head.
9.4
Service Manual - Rocket
III