TM 5-3810-300-24&P-3
15.1 Preventive Maintenance
35. Blower Screen
b. Turn the fan drive back so the inspection hole is
3/4" below the horizontal center line and add
Inspect the blower screen and, if necessary, clean the
fluid until the overflow point is reached. Replace
screen in fuel oil and dry it with compressed air. Install
the inspection plug.
the screen and gasket assembly with the screen side of
the assembly towards the blower. Inspect for evidence
NOTE: Use only the manufacturer's
of blower seal leakage.
Special 20 Cenistroke fluid.
36. Fan (Thermo-Modulated)
B. DRIVE BEARING LUBRICATION:
A. DRIVE FLUID LEVEL:
The fan drive bearing should be lubricated as outlined in
the chart with a Medium Consistency Silicone Grease
Check the fan drive fluid level to avoid improper
(Dow Corning No. 44, or equivalent).
operation and damage to the drive components.
The bearing on current fan assemblies is lubricated
Current modulated fan drive housings have an inspection
through a grease fitting in the drive housing hub.
plug for checking the fluid level.
Formerly partial
Lubrication of the bearing in former assemblies requires
disassembly of the drive was necessary to make the fluid
the removal of the fan assembly and partial disassembly.
level check. Former units can be updated by installing a
The former assemblies can be updated to include a
current drive housing which includes the fluid inspection
grease fitting by installing the current housing.
plug and a grease fitting for lubricating the bearing.
37. Crankcase Breather
1. Check the fan drive fluid level after the unit has
been idle for at least 1/2 hour.
The crankcase breather assembly is mounted on the
flywheel housing or the valve rocker cover. Clean the
2. Turn the fan drive so that the inspection plug is 3/4"
breather pads annually.
Remove the steel mesh
below the horizontal center line, then allow the silicone
breather pads from the engine; wash them in fuel oil and
fluid to drain down an additional five minutes.
dry with compressed air. The cleaning period may be
reduced or lengthened depending upon severity of
3. Remove the inspection plug. If fluid begins to flow
operating conditions.
from the inspection hole, the drive has sufficient fluid.
Replace the inspection plug.
38. Engine Tune-Up
4. If the fluid does not flow from the hole, proceed as
follows:
Minor adjustments such as injector timing, exhaust valve
clearance, governor and throttle delay (Items 26, 27 and
a. Rotate the fan drive downward and observe
32) should be made every 50,000 miles to compensate
when the fluid begins to flow from the hole.
for normal wear on parts. There is no scheduled interval
If it is necessary to lower the drain hole
for performing a complete engine. tune-up. As long as
more than 2" below the horizontal center line, the
the engine performance is satisfactory, a complete tune-
fan drive should be removed from the engine,
up should not be required.
disassembled and inspected for possible
damage to the components.
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