TM-9-2350-311-20-2 Maintenance Manual Volume 2 for M109 Cab Download
Page 189 of 828
TM 9–2350–311–20–2 3–78 3–3 TROUBLESHOOTING — CONTINUED f. RAMMER HYDRAULIC SYSTEM The rammer hydraulic system consists of the rammer, actuating valve, tray assembly, rammer cylinder, main release han- dle, cylinder handle assembly, cylinder latch, and the blocking valve. The rammer is used for loading and ramming the projectile into the tube. Hydraulic power from the power pack supplies the pressure to the rammer cylinder which rams the projectile into position. Normal hydraulic pressure is between 925 to 1225 psi (6378 to 8446 kPa). The rammer actuating valve controls the inflow of hydraulic fluid for the ramming operation and outflow of hydraulic fluid for the retraction of the rammer after use. The tray assembly holds the projectile in position for ramming while the cylinder latch locks the rammer cylinder into position on the tray assembly. The rammer cylinder con- tains a piston which rams the projectile into the chamber. The main release handle releases the locking mechanism so that the rammer may be moved into RAM position, and also back into STOW position. The cylinder handle assembly provides a hand hold for rotating the rammer cylinder into ramming position. The blocking valve prevents accidental ramming of ram- mer in stowed position. ACTUATING VALVE BLOCKING VALVE RAMMER ASSEMBLY MAIN ACCUMULATOR POWER PACK ASSEMBLY POWER RELAY BOX ASSEMBLY SLIP RING ELECTRICAL CONTACT HOLDER OPERATING PRESSURE 900 PSI (6206 kPa) DRAIN RESERVOIR PRESSURE 0 PSI (0 kPa) PUMP PRES- SURE 925–1225 PSI (6378–8446 kPa) GUNNER’S SELECTOR SWITCH BOX ASSEMBLY