Table 5-2. Direct Support Troubleshooting-continued -706880693

TM 5-4210-233-14&P-1

Table 5-2. Direct Support Troubleshooting - Continued

MALFUNCTION

TEST OR INSPECTION

CORRECTIVE ACTION

FIREFIGHTING SYSTEM - Continued

PRESSURE WILL NOT RETURN TO ORIGINAL SETTING AFTER DISCHARGE VALVES

ARE RE-OPENED

Pilot valve sticking.

Disassemble and clean (see para 4-36). Replace noticeaby worn parts.

HUNTING (FLUCTUATING PRESSURE)

Sticky pilot valve or faulty relief valve.

Disassemble and clean (see para 4-35 and 4-36). Replace worn parts.

AIR OPERATED VALVE (FOR AERIAL DISCHARGE) FAILS TO OPEN OR CLOSE

Step 1. Aerial discharge valve failed in open or closed position.

Remove pneumatic actuator and use a wrench on the valve shaft to open or close the valve

manually. If the valve does not move freely, replace the valve (see para 4-199).

Step 2. Pneumatic actuator defective.

Replace actuator (see para 4-200).

Step 3. Pneumatic actuator switch defective.

Replace pneumatic actuator switch (see para 4-179).

HYDRAULIC SYSTEM

OUTRIGGERS WILL NOT OPERATE

Step 1. Check power take-off operation.

Refer to hydraulic component testing (see para 5-50).

Step 2. Main hydraulic pump not operating.

Refer to hydraulic system component testing (see para 5-50).

Step 3. Pressure reducing (de-stroking) valve malfunctioning.

Refer to hydraulic system component testing (see para 5-50).

Step 4. Diverter valve malfunctioning.

Replace diverter valve (see para 4-193).

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