ohms, replace the transmitter. Crank
decreases to approximately 70 ohms. If
resistance does not decrease, replace
Replacement. (See figure 4-45.)
(1) Remove nut, washers, and lead from
transmitter threaded terminal.
(2) Unscrew transmitter from engine block.
(3) Install transmitter onto engine block.
(4) Reconnect electrical lead using nut and
4-73. PRESSURE SWITCH. (See figure 4-40.) There
are three pressure switches labeled no. 1, 2, and 3 on
Inspection. Inspect pressure switches (see
connection, dents, and leakage.
Test OP1. (See figure 4-46 and FO-3.)
MAINTENANCE LOCKOUT switch set to
OPERATION, connect miltimeter (set to
measure DC volts) from terminal 26 of TB6
to terminal 12 of TB9; multimeter should
read 24V DC.
multimeter reading should drop to zero
Test OP2. (See figure 4-46 and FO-3.)
(1) With generator set at shutdown, connect an
ohmmeter (set to Rx1 scale) from terminal 7
to terminal 12 of TB22; multimeter reading
should be less than 1 ohm.
(2) As engine is being cranked, ohmmeter
reading should jump to infinite ohms.
Test OP3. (See figure 4-46 and FO-3.)
(1) With generator set at shutdown, connect
ohmmeter from terminal 18 of TB20 to any
convenient ground connection; ohmmeter
reading should be infinite ohms.
(2) Crank engine and observe ohmmeter;
ohmmeter reading should drop to less than
1 ohm almost immediately.
Replacement. (See figure 4-46.)
(1) Disconnect leads from switch (1, 2, or 3).
(2) Unscrew switch (1 or 2) from engine block.
(3) For reassembly, screw switch into engine
block and tighten to 20 foot- pounds (27
joules). Reconnect leads to switch.
4-74. OIL FILTERS. (See figure 4-47.)
Spin-on Type Filters. Refer to paragraph 4-8 c
for replacement of spin-on type oil filters.
Bypass Oil Filters. (See figure 4-47.) Inspect
filter case for dents, cracks, and oil leaks. If
damaged, refer to higher maintenance.
4-75. SECONDARY FUEL FILTER ELEMENT.
(See figure 4-40.)
Service and replacement of the secondary fuel
filter element is as follows (see figure 4-48).
(1) Unscrew and remove the filter case and
discard filter element and gasket.
(2) Inspect the filter case for dents and cracks
that affect proper sealing when reinstalled.
If damaged, replace unit.
(3) Clean filter case. Handle or store in manner
to prevent out-of-round.
(4) Insert new element in filter case seating it