SECTION IV. TROUBLESHOOTING - TM-55-4920-442-13-P0040

TM 55-4920-442-13 & P

SECTION IV. TROUBLESHOOTING

3-13. Troubleshooting. In the event that operation of the test stand becomes faulty or erratic, refer to the

troubleshooting chart, table 3-3; to aid in isolating and correcting troubles.

Table 3-3. Troubleshooting Chart

MALFUNCTION

INSPECT

CORRECTIVE ACTION

Failure of high

Low fluid content in

Refill reservoirs to

pressure pump

test stand or aircraft

specified level.

reservoirs

Note: Low boost

Air leak in boost pump

Check and tighten all

pressure will shut

intake line

fittings.

down test stand

Boost pump not primed

Bleed air thoroughly from

cooler and filters.

Mechanical failure of

Replace pump. See

pump

Para. 3-64.

Shaft seal

leakage of pump

Replace pump. See

Para. 3-64.

Pump fails to deliver

Incorrect operating

Check correct operating

sufficient volume

procedures

procedure. See Chapter 2.

Also check volume control.

See Para. 3-68.

Pump seizure due to

Maintain adequate supply

lack of fluid supply

of hydraulic fluid in test

stand or aircraft reser-

voirs. Replace pump. See

Para. 3-64.

Defective high

Remove and service or

pressure relief valve

replace. See Para. 3-71,

3-72, 3-73 and Figure

C-14.

Pump fails to

Incorrect operating

Check correct operating

compensate

procedure

procedure. See Chapter 2.

Compensator assembly

Disassemble compensator

inoperative

assembly; check parts;

clean and reassemble.

See Para. 3-68, 3-69 and 3-

70.

Change 1 3-9