oIl Cooler
All GTH/GTV-760/990 V-Twin engines are equipped with an
oil cooler, which is mounted on the blower housing. Forced
air from the flywheel fan flows through the oil cooler fins dis-
sipating heat from the engine oil (see Figure 8-5) .
The oil cooler fins should be cleaned every 100 hours (or
more often under dusty conditions) and checked periodically
for debris. Clean with compressed air or a soft bristle brush.
Figure 8-5. Oil Cooler
oIl PuMP
All Generac engines utilize a gerotor style oil pump which is
classified as a positive displacement pump. Every revolution of
the pump will displace a constant amount of oil. As the inner
rotor turns, oil is drawn into the oil intake and fills the entire
cavity between the inner and the outer rotor. As the gerotor
continues to rotate, oil is moved from the intake port to the
outlet port where the oil is pushed under pressure throughout
the entire lubrication system (see Figure 8-6).
PreSSure relIeF vAlveS
When a constant displacement pump is used, a relief valve
is necessary to relieve the build-up of pressure in the system.
Relief valves are needed because the pump supplies more
pressurized oil than the system is able to use.
Generac uses two relief valves; a "Cold Start" and a
"Common" valve. When the oil is cold and the engine is
started, the oil pressure can reach up to 140 psi. To avoid
damage to the oil filter and oil cooler, the "Cold Start" relief
valve is installed in series immediately downstream of the oil
pump and is set at 60 psi. After the oil goes through the oil
cooler and filter, it flows through the "Common" relief valve.
This relief valve is set at 40 psi and mainly regulates the pres-
sure to the PTO journal and then throughout the rest of the
oil system (Figure 8-7 and 8-8).
CAMSHAFT
PUMP COVER
PUMP BODY
PICK-UP
SCREEN
OUTER ROTOR
INNER ROTOR
Figure 8-6. Oil Pump, Vertical Engine
PICK-UP SCREEN
COLD START
RELIEF VALVE
(60 psi)
COMMON
RELIEF VALVE
(40 psi)
Figure 8-7. Oil Pump, Horizontal Engine
SeCTIoN 8: lubrICATIoN SYSTeM
8-3
8
Содержание GTH760
Страница 28: ...3 12 Notes ...
Страница 46: ...NOTES 6 8 ...
Страница 52: ...Section 8 Lubrication System 8 4 Figure 8 8 Typical V twin Engine Oil Flow Vertical Shaft Engine Shown ...
Страница 60: ...Notes ...
Страница 64: ...Notes ...
Страница 73: ...Notes ...
Страница 74: ...Notes ...
Страница 75: ......
Страница 76: ...Generac Power Systems Inc P O Box 297 Whitewater WI 53190 Part No 0F6923 Printed in USA Revision C 08 13 08 ...