RECOVERY VEHICLE, FULL TRACKED: MEDIUM, M88A1
MECHANICAL TRANSMISSION AND MAIN HYDRAULIC PUMP CIRCUIT (MAIN HYDRAULIC SYSTEM)
Tools and Special Tools
Mechanical transmission and Main Hydraulic Pump Circuit (Main Hydraulic System)
Mechanical transmission and main hydraulic pump circuit (main hydraulic system) malfunctioning.
Mechanical transmission fails to operate.
Do steps 1 thru 4.
Main hydraulic pump fails to engage.
Do steps 5 and 6.
Mechanical transmission overheating.
Do steps 7 thru 9.
Mechanical transmission slipping or chattering.
Do step 10.
Mechanical transmission fails to disengage main hydraulic pump. Do steps 11 and 12.
Main hydraulic pump noisy. Do steps 13 thru 15.
Inspect mechanical transmission drive shaft.
Inspect mechanical transmission for broken or restricted hose.
Replace mechanical transmission hose (TM 9-2350-256-20).
Inspect mechanical transmission output shaft to main hydraulic pump. If not rotating, proceed with
mechanical transmission clutch pressure check. Install pressure gage in mechanical transmission
clutch pressure line. For location, refer to TM 9-2350-256-20. With engine operating at 1800 rpm and
power control valve lever in ON position, normal operating pressure is 150 10 psi (1034 69 kPa).
Remove mechanical transmission and main hydraulic pump assembly (WP 0065 00).
Test for defective power control valve or restricted hose. Remove hose no. 66 from mechanical
transmission. With mechanical transmission drive shaft rotating, and power control valve lever placed
in ON position, oil should flow from hose.