TM 55-4920-384-13&P
on the cylinders and heads, should be thoroughly
cleaned of all dirt and other deposits.
The air cleaner should be cleaned of all oil and ac-
cumulated dust, and the sediment removed from the
oil cup at the bottom of the cleaner.
To protect the cylinders, pistons, rings and valves
and keep them from rusting and sticking, a rust pre-
ventative oil, as specified under Military Specifica-
tion MIL-0-6082, (Type 1, ready mixed, or equivalent)
should be injected into the pipe tap opening on the
at moderate speed. About a quarter of a pint is nec-
essary on a four cylinder engine, or enough so that a
heavy bluish smoke will appear at the exhaust. The
ignition switch should then be shut off and the en-
gine stopped. This operation will leave a coating of
oil on the above mentioned parts, protecting them
from the atmosphere.
On engines where the pipe tap opening on the intake
manifold is inaccessible, the rust preventative may
b e injected into the air intake on the carburetor
while the engine is running. The air cleaner connec-
tion will of course have to be disconnected from the
carburetor to do this.
OIL FITTING
OIL LEVEL PLUG
104576C
Remove plug from crankcase bottom cover and drain
oil. Drain while engine is warm, as the oil will then
The throwout collar should be lubricated once a day
flow much more freely than when cold.
before starting. Add grease to fitting on side of hous-
ing, as illustrated in Fig. 39, using the same type
Drain fuel system, including gasoline lines, carbu-
grease as used in the clutch power take-off units.
retor, fuel pump and tank of all gasoline, to prevent
Twin Disc units have an external grease fitting for
lead and gum deposits from forming.
the throwout bearing.
All exposed unpainted metal parts should be coated
The shifter shaft should be lubricated periodically,
with grease or heavy oil.
if external oil fittings are provided for this purpose.
The air cleaner or carburetor intake, as well as the
exhaust manifold and breather openings, should be
The reduction unit is operated in oil and the gear
taped or otherwise sealed off for the duration of the
case oil level must be maintained to the oil saber
storage period.
gauge or
plug, see Fig. 39. In
Twin Disc units, high
grade transmission oil S.A.E. No. 90 to No. 110 Vis-
Before starting the engine after the storage period,
cosity must be used. For Rockford units, use No. 30
remove crankcase drain plug so that any condensa-
S. A. E. crankcase oil. Change oil every 2000 hours
tion which may have collected may be drained before
of service, while unit is warm.
new crankcase oil is added. It is highly recommend-
ed that the crankcase bottom cover be removed be-
If clutch slips, heats, or operating lever jumps out,
fore starting the engine, and scrubbing off all sedi-
the clutch must be adjusted. Release clutch operat-
ment which may have collected there. When reassem-
ing lever and remove hand hole plate. The clutch in
bling the bottom cover a new gasket should be used.
the clutch reduction units is the same as is used in
the clutch power take-off units. Refer to "Clutch Ad-
justment" paragraph for adjustment of the clutch in
Be sure to fill crankcase with the correct grade
of oil to the full mark on the saber. Do not use
the Twin Disc and Rockford clutch reduction units.
A new clutch generally requires several adjustments
any oil heavier than SAE No. 30. Also be sure
until the friction surfaces are worn in.
to put oil to the proper level in the air cleaner.
(Refer to Lubrication and Air Cleaner.)
INSTRUCTIONS FOR PROTECTING ENGINE
Refuel engine and follow the starting instructions as
DURING PERIODS OF STORAGE
shown on preceding pages of this manual.
When the work interval is completed, the following
It is suggested that machines be stored inside
instructions should be carried out very carefully to
a building. If this is not possible, the engine
protect the engine during the storage period.
should be protected from the weather by a proper
The outside of the engine, including the cooling fins
covering.
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