TM 10-4610-232-34
Table 2-1. Direct Support Troubleshooting Guide
MALFUNCTION
TEST OR INSPECTION
CORRECTIVE ACTION
RAW WATER PUMP.
1. Raw water pump assembly is noisy.
Step 1. Check for foreign objects in pump.
Disassemble pump (para. 2-11).
Step 2. Inspect pump internals for wear and damage.
Replace worn or damaged parts (para. 2-11).
Step 3. Turn the motor shaft by hand. It should turn easily, without noise, without dragging, and without rough spots.
If rotation is not smooth, bearings are bad. Replace motor bearings (para. 2-12).
2. Raw water pump runs but will not prime. Raw water pump does not supply sufficient pressure or flow.
Check pump internals for wear and damage.
Replace worn or damaged parts (para. 2-11).
3. Raw water pump motor hums but won’t turn.
Step 1.
Step 2.
Step 3.
Step 4.
Step 5.
Step 6.
Check for foreign objects in pump.
Disassemble pump (para. 2-11).
Inspect pump internals for wear and damage.
Replace worn or damaged parts (para. 2-11).
Tag and disconnect motor leads (T1, T2, T3) (REF: Interconnection diagram FO-2, Sheet 10). Set multimeter
to Ohms x 1000 scale and connect test leads between each motor lead and the motor frame. Readings should
be infinity for each step.
Replace motor if the meter reading is zero (para. 2-12).
Set multimeter to Ohms x 1 scale and check for continuity between all pairs of motor leads, T1 and T2, T1 and
T3, T2 and T3. Readings should be zero or near zero for each step.
Replace motor if reading is infinity (para. 2-12).
Turn the motor shaft by hand. It should turn easily, without noise, without dragging, and without rough spots.
If rotation is not smooth, bearings are bad. Replace motor bearings (para. 2-12).
Refer to raw water pump electrical troubleshooting (malfunction 4).
AIR BLOWDOWN SOLENOID VALVE.
Air blowdown solenoid valve leaks air when it should be closed.
Check valve for plugging or damage.
(a) Remove valve from piping and disassemble (para. 2-51).
(b) Clean out valve and inspect for wear.
(c) If necessary, replace valve stem and seat (para. 2-51).
(d) If necessary, replace valve and solenoid assembly (para. 2-51).
AIR COMPRESSOR.
1. Air compressor oil has water in it (looks milky).
Visually inspect that there is oil and water mixed.
Send to General Support Maintenance and have them inspect/repair pistons and piston rings.
Change 1 2-3
