Table IV. Periodic Inspection and Service (Cont)
Inspection and Service
4. Hydraulic System:
a. High Pressure Filter
Check for dirty or clogged element. See paragraph 4-7.
b. Low Pressure Filter
100 HOUR INSPECTION
1. Fuel System
Clean and service fuel pump. See paragraph 4-10.
Check ignition timing. See paragraph 4-11.
b. Magneto points
Check magneto point condition and gap. See paragraph 4-12.
Check for proper temperature response. See paragraph 4-14.
4. Hydraulic Reservoir
Drain and Clean. See paragraph 4-15.
d. Check condition of bowl gasket and replace if
Replace badly worn or cracked spark plugs.
necessary. Reassemble parts and open fuel valve.
c. Check and adjust spark plug gap. Gap should be
4-4. SERVICING ENGINE OIL FILTER. Service the engine oil
filter (9, figure 1-3) as follows:
d. Install spark plugs. Plug thread is 18 millimeter.
Remove cover and cover gasket.
Tighten spark plugs to 25-30 foot pounds torque.
b. Remove cartridge. Clean out sludge from filter body.
4-7. SERVICING HIGH PRESSURE FILTER. If filter element
Do not remove spacer from center tube.
of high pressure filter (5, figure 1-3) is clogged or dirty, replace
element as follows:
Install new cartridge and cover gasket. Install cover.
a. Cut safety wire and unscrew element case from
d. Add oil to compensate for filter. Run engine for five
bottom of filter head.
minutes and check for leaks. Recheck oil level.
b. Remove old element and thoroughly clean case.
4-5. SERVICING AIR CLEANER.
Service the engine air
Install new element in case.
cleaner (11, figure 1-3) as follows:
c. Thread case with element into bottom of filter head.
a. Loosen clamp screw and remove bowl from bottom of
Secure with safety wire.
4-8. CHECKING LOW PRESSURE FILTER. Perform the
b. Clean bowl and refill with oil, Military Specification
following low pressure filter (7, figure 1-3) condition checkout
MIL-L-2104 to oil level line. Install bowl to bottom of cleaner
while Test Stand is in operation with flow set at 10 gpm.
and secure with clamp screw.
a. Place pressure selector valve (12, figure 3-1) in
c. Remove precleaner from top of cleaner assembly and
FILTER INLET position. Observe reading on low pressure
empty accumulated dirt. Do not use oil or water in precleaner.
gage (9). Record this reading.
d. At least once a year, remove air cleaner from engine
b. Place selector valve (12) in FILTER OUTLET position.
and wash element (not removable) in solvent to clean out
Observe reading on low pressure gage (9). Record this
accumulated dust and dirt.
4-6. SERVICING SPARK PLUGS. Service engine spark plugs
c. Subtract second reading from first reading. The result
of this subtraction is the pressure drop across the low pressure
filter. A pressure drop of 20 psi or more indicates a clogged
a. Remove spark plugs
filter element. Replace filter element as outlined in paragraph
thoroughly inside and out.