HYDRAULIC LIFT SYSTEM TROUBLESHOOTING (cont)

TM 10-3930-638-24&P 2-55. HYDRAULIC LIFT SYSTEM TROUBLESHOOTING (cont) MALFUNCTION TEST OR INSPECTION CORRECTIVE ACTION 1. LOAD LOWERS TOO FAST (cont) Step 2. Lower mast assembly to ground. Turn engine off and relieve hydraulic pressure by operating control levers several times. Place container under lift cylinder to catch hydraulic oil. Loosen and disconnect fitting at lift cylinder port; remove elbow. Check that restrictor is properly installed: FLOW arrow marked on restrictor pointing towards lift cylinder assembly. a. If restrictor is not installed properly, install properly. b. If restrictor is installed properly and problem still exists, replace restrictor. 2. LOAD CREEPS DOWNWARD Step 1. Check hoses, lines and fittings between control valve and lift cylinder assembly for oil leaks. a. If oil leakage is observed, tighten fittings; if hoses or lines are damaged, replace (para 2-56f(1)). b. If oil leakage is not observed, proceed to step 2. Step 2. Check if lift cylinder assembly requires bleeding of air (para 2-56f(1), step 27). a. Bleed air from lift cylinder assembly (para 2-56f(1), step 27). b. If lift cylinder does not require bleeding of air, proceed to step 3. Step 3. Perform step 2 of MALFUNCTION 1 above. Same as step 2 of MALFUNCTION 1 above. 3. UNABLE TO LIFT, TILT, SHIFT OR ROTATE LOAD Step 1. Check hydraulic reservoir oil level a. If oil level is not between FULL and ADD marks on dipstick with mast lowered, add hydraulic oil (refer to current lubrication order). b. If oil level is okay, proceed to step 2. Step 2. Start engine and operate control levers while observing HYDRAULIC FILTER indicator light on instrument panel. a. If HYDRAULIC FILTER indicator is lit, replace hydraulic oil filter (para 2-56g(2)). b. If HYDRAULIC FILTER indicator is not lit, turn engine off, place IGNITION switch in LAMP TEST position and check that HYDRAULIC FILTER indicator is on. If HYDRAULIC FILTER indicator is on, proceed to step 3. If HYDRAULIC FILTER indicator is not on, replace bulb (para 2-28e), and repeat this step. 2-390