Section 9: Lubrication System - Generac Power Systems OHVI GSH 220 Service Manual

GeNerAl
The engine lubrication system serves to
between moving parts, (b) cool the engine and (c) establish a
negative pressure in the crankcase to prevent oil seal leakage.
Major components include the following:
• Oil pickup assembly.
• Oil pump.
• Crankshaft oil seals.
• Pressure relief valve.
• Breather assembly.
• Crankcase cover.
• Low Oil Pressure Switch.
OPTIONAL SYSTEMS:
In addition to the major components listed above, some
engines may be equipped with an optional oil filter.
oIl Flow
(410CC, lArGe FrAMe eNGINeS)
See Figure 9-. An oil pickup screen extends into the
crankcase. The oil pump draws crankcase oil through the oil
pickup screen and delivers it to the areas requiring lubrication
as follows:
. If so equipped, oil will pass through an oil filter and through
a cored passage in the crankcase cover.
2. The cored passage in the crankcase cover allows oil to reach
the oil pump and one camshaft bearing surface. Oil flows
through the cored passage in the cover and also flows to
one crankshaft bearing and one balancer bearing.
. Oil flows through the hollow camshaft to lubricate the
camshaft bearing at the opposite end of the camshaft.
. Oil from the end of the camshaft enters a cored passage
and flows to one crankshaft bearing and one balancer
bearing.
5. Oil flows through the crankshaft and to the crank throw
to lubricate the rod bearing.
6. If oil pressure exceeds 0 psi. The oil pressure relief valve
opens.
If not equipped with an oil filter, oil flows through a cored
passage in the crankcase cover and then to the oil pump. Oil
flow is then identical to units having an oil filter.
(a) reduce friction
See Figure 9-2. The oil pump draws crankcase oil through
an oil pickup and delivers it to the areas requiring lubrication
as follows:
. Through a cored channel in the crankcase cover and to
the crankshaft journal at the power take-off (PTO) end of
the crankshaft.
2. Through the hollow camshaft and to the camshaft bearing
at the flywheel end.
. Through a cored passage in the crankcase housing and to
the crankshaft journal at the flywheel end.
. Through the crankshaft to the crankpin and connecting
rod bearing.
5. If oil pressure exceeds 0 psi, the oil pressure relief valve
opens.
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SeCTIoN 9: lubrICATIoN SYSTeM

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BALANCER BEARINGS
NOT VISIBLE IN THIS VIEW
Figure 9-1. Lubrication System Diagram
(410cc, Large Frame Engine)
oIl Flow
(220CC, SMAll FrAMe eNGINeS)
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