TM 55-4920-384-13&P
that under these conditions the maximum pressure
will be limited to 15 pounds.
OIL FILTER
A Military oil filter, as illustrated in Fig. 4, is fur-
nished on both the open engine and power unit, built
to MIL-E- 11275-C and MIL-E- 11275-B specifications.
The oil filtering cartridge should be replaced after
every 100 hours of operation, under normal operating
conditions. If engine is operated under extreme dusty
conditions, replace cartridge after every oil change.
Refer to accessory section in the rear of the manual
for further service instruction and replacement parts.
A Wisconsin commercially used by-pass type oil filter
is used on MIL-E- 11275-A spec engines. This filter
is mounted on the left hand side of the crankcase,
next to the magneto, as illustrated in parts list sec-
The filter cartridge should be replaced after every
other oil change. If operating conditions are extreme-
ly dusty, replace cartridge after every oil change.
Part number is located on top of cartridge, for re-
placement identification.
FUEL
These engines can be furnished "with a gravity feed
tank mounted above the level of the carburetor, or
with a side mount tank. In all cases a fuel pump is
GRADE OF OIL CHART
furnished on the engine.
The fuel tank should be filled with a good quality of
gasoline free from dirt and water. Some of the poorer
grades of gasoline contain gum which will deposit
on valve stems, piston rings, and in various small
passages in the carburetor and thus cause serious
trouble in operating, and in fact might prevent the
engine from operating at all.
Use gasoline that conforms to Military Specifi-
cations MIL-G-3056 or MIL-F-5572.
FUEL PUMP
All engines are equipped with a fuel pump. When start-
ing a new engine for the first time, or when engines
GRADE OF OIL
Follow summer recommendations in winter if engine
is housed in warm building.
Check oil level every 8 hours of operation.
The old oil should be drained and fresh oil add-
ed after every 50 hours of operation.
To drain oil, remove drain plug illustrated in Fig. 4.
Oil should be drained while engine is hot, as it will
then flow more freely.
OIL PRESSURE
At engine operating temperature the oil pressure will
be about 4 to 5 pounds per square inch. Due to this
quired. When the engine is cold the pressure will be
D-9