TM-5-2350-378-24-P
HYDRAULIC DIAGNOSTIC CENTER (HDC) SUPPORTING ARMORED COMBAT EARTHMOVER (ACE), M9
TECHNICAL MANUAL; UNIT, DIRECT SUPPORT, AND GENERAL SUPPORT MAINTENANCE MANUAL INCLUDING REPAIR PARTS AND SPECIAL TOOLS LIST
TM-5-2350-378-24-P - Page 27 of 790
TM 5--2350--378--24&P
0004 00--2
INTRODUCTION TO TROUBLESHOOTING AND REPAIR OF THE M9 ACE HYDRAULIC
SYSTEM -- Continued
0004 00
LOCATION AND DESCRIPTION OF MAJOR COMPONENTS -- CONTINUED
Figure 4. M9 ACE Hydraulic System Major Components
(1) MAIN HYDRAULIC PUMP. Fixed displacement pump that pulls hydraulic oil from the reservoir to perform
whatever function is necessary
(2) MAIN ACCUMULATOR. Helps keep pressure constant in hydropneumatic suspension system.
(3) SPRUNG/UNSPRUNG VALVE. Regulates pressurized fluid flow for whichever mode is selected.
(4) HYDRAULIC RESERVOIR. Supplies hydraulic oil through main pump, high--pressure filters, and directional
control valve to activate hydraulic functions of vehicle.
(5) NO.1AND4ACTUATORS. Front:providesvehiclesuspensioninSPRUNGmodeandallowsvehicletoraise
and lower in UNSPRUNG mode. Rear: No. 4 is same as front, except they cannot be raised or lowered.
(6) NO.2 AND 3 ACTUATORS. Operate offNo.1 and 4 actuators. Interwheel controlvalves allow them to follow,
rather than lead No. 1 and 4 actuators when vehicle is lowered.
(7) SUSPENSION RELIEF VALVE. Relieves pressure surges or gradual increases in pressure to suspension.
(8) BUMP STOP CYLINDERS. Limit upward travel of roadwheel arms when in SPRUNG position (one on each
side).
(9) INTERMEDIATE WHEEL VALVE. Prevents No. 2 and 3 actuators from raising when lowering front ofvehicle.
(10) EJECTOR CYLINDER. Moves ejector forward and back with hydraulic pressure.
(11) CHECK VALVE. A device to control the direction of fluid flow.
(12) COMPENSATINGPUMP. ProvidespressuretovehicleforSPRUNG/UNSPRUNGhydraulic
operation.
Back to Top
