HYDRAULIC STARTING SYSTEM - TM-55-1905-217-120121

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HIGH COOLANT TEMPERATURE

TM-55-1905-217-12 Landing Craft Mechanized; Steel; DED; Overait Length 74 Feet Mod 1 Marl VIII Navy Design LCM-8 Hull Numbers 8500 and 8580 thru 8618 Manual

STEERING IS SLOW

TM 55-1905-217-12

MALFUNCTION

TEST OR INSPECTION

CORRECTIVE ACTION

Step 4. Check if starter brushes are worn.

Replace brushes (para 4-80).

HYDRAULIC STARTING SYSTEM

1. ENGINE DRIVEN PUMP FAILS TO RAISE PRESSURE

Step 1. Check for air in system.

Purge system (para 4-58).

Step 2. Check if filter is plugged.

Replace filter element (para 4-69).

Step 3. Check if check valves are functioning properly.

Open the relief valve on the side of the hand pump, while the engine is running, to permit

the engine driven pump to wash the check valves free from particles. If the accumulator

can be charged with the hand pump but not with the engine driven pump, then a check

valve in the engine pump is defective. Replace the faulty check valve assembly (para 4-67).

2. CRANKING SPEED TOO LOW

Step 1. Check if control valve is fully open.

Check control valve, replace if necessary (paras 4-64 and 4-65).

Step 2. Check if inlet line is restricted.

Check lines for foreign matter (para 4-81).

3. LOSS OF FLUID FROM RESERVOIR

Step 1. Check for external leaks.

With pressure in system check air hoses and fittings for leaks. Tighten and replace defective

part

Step 2. Check for internal leaks.

Check level of oil in reduction gears. A leaking seal in the hydrostarter will allow hy-

draulic fluid from the starter system to enter the reduction gear case. Replace starter,

drain transmission oil, and flush. Replace filter and fill with clean oil.

4. LOSS OF FLUID PRESSURE WHEN ENGINE IS NOT RUNNING

Step ,1. Check for external leakage in system.

Examine all hoses and fittings for leaks. Tighten or replace fittings and any defective parts

(para 4-57).

5. HAND PUMP FAILS TO CHARGE SYSTEM

Step 1. Check if check valves are leaking.

If caused by dirt, open relief valve (maximum of one (1) turn), and operate hand

pump slowly for a few minutes to wash particles out of check valves. If this is success-

ful, clean ball seats in pump body and replace balls and springs if necessary (para 4-81).

Step 2. Check if suction line is plugged. Remove line and clean (para 4-60).

6. LOSS OF ACCUMULATOR PRECHARGE (NITROGEN)

Step 1. Check air valve.

Release pressure in system by opening relief valve on hand pump. Then depress air

valve to release remaining precharge before attempting to remove valve from acoumu-

lator. Replace air valve (para 4-60).

Step 2. Check safety fuse.

Replace safety fuse and holder gaskets (para 4-60).

7. HIGH PRESSURE IN SYSTEM (3500 PSI OR ABOVE)

Step 1. Check gage.

Replace gage (para 4-57).

8. FLUID EMERGES FROM RESERVOIR FILLER CAP WHEN HYDRAULIC STARTER IS USED

Step 1. Check for excessive fluid in reservoir.

Check fluid level after the accumulator is discharged. The fluid level should be approxi-

mately 2 1/2 in. from the top of the filling tube (para 4-57).

Step 2. Check if filter in filler cap is dirty.

Clean with fuel oil and blow dry (para 4-57).

STEERING SYSTEM

1. STEERING WHEEL DIFFICULT TO TURN

Step 1. Check if relief valve is stuck open.

Readjust relief valve (para 4-80) or (para 4-81).

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