ARMY TM 9-6115-604-12
NAVY NAVFAC P-8-633-12
Remove floor mat (53). Remove machine screws (48), and remove floor plates (49) from the skid
Remove electrical connector from fuel level switch FL1 through FL4 assembly (52).
Remove fuel level switch FL1 through FL4 assembly (52) from the fuel tank using spanner 383.
TEST. See figure 4-30
Set multimeter to RX1 scale and test switch In dry state across terminal sets E and D; F and C; G
and B; and D and A. Hold switch in upright vertical position. Resistance reading across terminals E
and D should be infinite ohms, while terminal sets F and C; G and B; and D and A should read zero
ohms in the dry state.
Immerse fuel level switch assembly (in upright vertical position) into a suitable graduated cylinder,
or equivalent, containing diesel fuel. Immerse switch to a level immediately below the threaded
tank fitting. Do not immerse connector end of the switch assembly. Connect multimeter (RX1 scale)
across same terminal sets in step (1), above. Terminals E and D should now read zero ohms. All
other terminal sets (F and C, G and B; and D and A) should now read Infinite ohms.
Connect multimeter leads across terminals E and D and slowly raise switch assembly to a level
approximately 0.8 inch below the bottom of the threaded tank fitting. Resistance across terminals E
and D should now read Infinite ohms as well as all other terminal sets.
Continue raising switch to a level approximately 1.9 Inches (5 mm) below threaded tank fitting.
Terminal sets D and E; G and B; and D and A should now read infinite ohms. Terminal sets F and C
should read zero ohms.
Continue raising switch to a level approximately 5 06 Inches (129 mm) below the threaded tank
fitting. Terminal sets E and D, and D and A should read infinite ohms Terminal sets F and C, and
G and B should read zero ohms.
Continue raising switch to a level approximately 6.5 inches (152 mm) from the bottom of the
threaded tank fitting Terminal sets F and C; G and B; and D and A should read zero ohms.
Terminals C) and E should read infinite ohms.
Replace fuel level switch assembly if it fails any test as described above.
Install. See Figure 4-31.
Install fuel level switch FL1 through FL4 assembly (52) in fuel tank using spanner 383.
Install electrical connector to fuel level switch FL1 through FL4 assembly (52).
Install floor plates (49) to the skid base with machine screws (48) install floor mat (53).
Install rear door stop plate (47) with hexagon head cap screws (44), hexagonal nuts (45), and lock
Install the control room fire extinguisher and bracket in accordance with paragraph 4-12.
Close fuel drain valve (34) and refill fuel tank.
Turn FUEL PUMP switch S8 on generator control cabinet C to HAND or AUTO as necessary.
MAINTENANCE OF FUEL QUANTITY TRANSMITTER MT4. The fuel quantity transmitter MT4 (12, Figure
3-6) is mounted In top of the fuel tank. The transmitter is a variable resistor which vanes resistance according to the fuel
float position. The transmitter is connected to FUEL LEVEL gage M4.
The fuel tank, even when empty, may contain explosive fumes or vapors. Do not
expose tank In vicinity of any source of intensive heat. Smoking is prohibited
within SO feet (15 meters) of the work area. Failure to heed this warning may
result in death or serious injury.