HYDRAULIC OIL FOAMING - TM-9-2320-285-24-10888

TM 9-2320-285-24-1

2-76. FIFTH WHEEL HYDRAULIC SYSTEM TROUBLESHOOTING (CONT)

MALFUNCTION

TEST OR INSPECTION

CORRECTIVE ACTION

4. FIFTH WHEEL DOESN'T LOWER

Try to raise and then slowly lower fifth wheel boom.

a. If fifth wheel boom lowers, velocity fuses had set (fifth wheel boom was lowered too quickly).

Raise and lower fifth wheel boom several times to ensure hydraulic system is functioning

properly.

b. If fifth wheel boom does not lower, notify direct support maintenance.

5. HYDRAULIC OIL FOAMING

Step 1.

Check for clogged suction filter element.

a. If filter element is clogged, replace (para 2-78b(1)).

b. If filter element is not clogged, go to step 2 below.

Step 2.

Check for obstructed hydraulic pump suction hose and fittings.

a. If suction hose and fittings are obstructed, replace (para 2-78b(1)).

b. If suction hose and fittings are not obstructed, notify direct support maintenance.

6. EXCESSIVE HYDRAULIC PUMP NOISE

WARNING

Do not remove filler cap when hydraulic oil is hot. Hot oil can cause

severe injury.

Remove hydraulic reservoir filler cap and check oil level.

a. If oil level is below bottom of filter screen, fill with hydraulic oil (para 2-78c) until level is at bottom

of filter screen.

b. If oil level is at bottom of filter screen, refer to Malfunction 5, step 1 above.

2-865