Table 4-1. Unit Troubleshooting-continued

TM 5-5430-226-12

Table 4-1. Unit Troubleshooting - cont.

MALFUNCTION

TEST OR INSPECTION

CORRECTIVE ACTION

2. VENT FITTING ASSEMBLY LEAKS.

WARNING

To prevent injury to personnel and damage to the equipment, do not open coupling lock arms

when water is stored in tank.

NOTE

Some tanks have a vent pipe with a cam-lock coupling at the base and some have a vent pipe

welded to the base. Maintenance instructions for vents with cam-lock couplings are given in

para. 4-14. Maintenance instructions for vents with welded bases are given in para. 4-19.

Step 1. Inspect for distorted, cracked, cut or missing vent cap gasket.

Replace vent cap (para. 4-14 or para. 4-19). See NOTE above.

Step 2. Inspect for bent or broken vent cap hinge pin.

Replace vent cap (para. 4-14 or para. 4-19). See NOTE above.

Step 3. Inspect vent pipe for cracks. If present, inspect coupling for cracks, broken locking arms, and damaged

or missing coupling gasket.

Replace vent pipe or coupling (para. 4-14 or para. 4-19). See NOTE above.

Step 4. Check for loose or missing bolts on water tank coupling half.

Replace missing bolts and washers.

Torque loose bolts to 30 inch-pounds. On tanks manufactured by Amfuel Company, torque loose bolts

to 40-60 inch-pounds.

Step 5. Remove flange from water tank (para. 4-14 or para. 4-19). See NOTE above. Inspect flanged

piece for cracks or scratched sealing surface. Inspect o-ring for cuts, tears, and distortion.

Replace coupling half, if damaged.

Replace o-ring, if damaged.

Step 6. Inspect water tank compression fitting for cuts, punctures, elongated holes and tears.

If compression fitting or tank fabric is damaged, replace water tank.

3. FILLER/DISCHARGE ASSEMBLY LEAKS.

Step 1. Inspect filler/discharge elbows for cracked, torn, distorted or missing coupling gaskets.

Replace elbows or coupling gaskets if damaged (para. 4-15).

4-6