Use of fully charged batteries or a slave unit with the 8-inch howitzer in retracted position:

TB 9-1000-234-13

6. By applying the strokes counted in extending the pin three times, the correct reserve of oil is placed

in the recuperator.

7. Place the retracting valve handle in the normal HOLD position.

8. Open the accumulator shut-off valve.

(b) Use of vehicle engine and engine-driven pump:

1. Start vehicle engine.

2. Place power take-off and pump switch to ON.

3. Place retractor valve handle in RETURN position.

4. After weapon has returned to battery, watch the oil index pin to see if it moves out. If pin fails to

move out before the automatic clutch disengages pump (caused by pressure in system reaching 2400 psi and pressure

switch opening), it means the pressure in recuperator is higher than motor driven pump (primary source). Place and hold

switch in the OVERRIDE position; this will bypass the pressure switch and start electric drive pump.

5. Watch the oil index pin. When it starts to move out, count the time interval required to move pin from

IN to OUT (fully extended). Now continue to hold OVERRIDE switch for a period of time twice as long as it is required to

move pin out This will establish reserve of oil.

6. Place retractor valve handle in normal HOLD position.

7. Turn off power take-off and pump switch.

8. Stop vehicle engine.

NOTE

The 8-inch howitzer can be filled with reserve oil without using the OVERRIDE switch because of

the lower pressure required in the recuperator.

1. Turn on master switch in driver's compartment.

2. Place electric motor driven pump switch to ON position.

3. Place retractor valve handle in RETURN position.

4. After weapon has returned to battery position and the 1600-2400 psi pressure switch has

automatically stopped the electric pump, and the oil index pin is still recessed in the IN position, place and hold switch in

the OVERRIDE position.

5. Watch the oil index pin. When it starts to move OUT, count the time interval required to bring pin to

the OUT position (fully extended -0.20 inch from face).

6. Continue to OVERRIDE pressure switch for a period of time twice as long as in step (5) above. This

will establish an oil reserve in recuperator.

7. Place retractor valve handle in the normal-HOLD position.

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