TM-9-2350-311-10

TM 9-2350-311-10

3-6

ARMAMENT AND CAB MAINTENANCE — CONTINUED

3-6.4

Zero Pressure Check and Checking, Filling, and Draining Power Pack — Continued

Procedure — Continued

Observe pressure gage (3). Normal operating pressure range is 925 to 1225 psi (6378 to 8446 kPa).

Turn CAB POWER switch (2) and MASTER switch (1) to OFF.

NOTE

Turret lock is in LOCKED position when word LOCKED is covered.

Move turret lock (4) to LOCKED position or place cannon tube in travel lock.

Turn TRAVERSE CONTROL switch (5) to MANUAL position.

Disconnect wire 645 (6) at quick disconnect (7) near pressure gage (3).

Turn MASTER switch (1) and CAB POWER switch (2) to ON.

NOTE

Perform steps 9 and 10 simultaneously.

Move gunner’s control handle (8) to left or right.

NOTE

If main accumulator nitrogen pressure is below 500 psi (3448 kPa), notify unit maintenance.

Normal precharged nitrogen pressure varies with temperature changes.

Watch pressure gage (3) needle (9) as it drops from operating pressure until it flutters, then drops

sharply to 0 psi (0 kPa). The reading at which the pressure gage needle fluttered is the amount of

precharged nitrogen in the main accumulator. Normal precharged nitrogen pressure in the main

accumulator will be 500 to 550 psi (3448 to 3792 kPa) at 70° F (21° C).

Turn CAB POWER switch (2) and MASTER switch (1) to OFF position.

Observe sight gage (10) on power pack assembly (11). Fluid appearing in gage should be level with

FULL AT ZERO PRESSURE mark (12).

Check and fill power pack assembly (11) (item 4, Appx G) as required.

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