TM  10-3930-638-24&P 3-29.   HYDRAULIC   LIFT   SYSTEM   TORUBLESHOOTING   (cont) MALFUNCTION TEST  OR  INSPECTION CORRECTIVE ACTION 1. UNABLE TO LIFT A LOAD (ALL OTHER FUNCTIONS NORMAL) (cont) Step 3. With engine at idle speed and LIFT control lever in RAISE position (mast assembly will be at full height), check for hydraulic oil leakage at gland assembly (located at bottom of lift cylinder assembly) and at ring assembly (located at bottom of lift cylinder body). a. If hydraulic oil leakage is observed, remove lift cylinder assembly (para 3-30e), and repair or replace gland assembly or ring assembly (para 3-30e). b. If hydraulic oil leakage is not observed, proceed to step 4. Step 4. Start engine and operate at idle speed. NOTE Increase engine speed as necessary to prevent engine stall. Place LIFT control lever in RAISE position and hold (mast assembly will be at full height). Check control valve for hydraulic oil leakage. a. Replace or repair control valve (para 3-30a) if hydraulic oil leakage is observed. b. If hydraulic oil leakage is not observed, proceed to step 5. Step 5. With engine off, operate control levers several times to relieve hydraulic pressure. Disconnect hose assembly connected between control valve and lift cylinder assembly at con- trol  valve  (refer  to  illustration). Connect a 3000 PSI pressure gage between elbow on control valve and hose assembly. NOTE Increase engine speed as necessary to prevent engine stall. Start engine and place LIFT control lever in RAISE position until mast assembly is at full height; continue to hold lever in RAISE posi- tion. Pressure gage shall indicate 2500-2550 PSI with  engine  at  full  throttle. a. b . If pressure gage indication is above or below  2500-2550  PSI,  adjust  pressure relief valve (para 2-48 b(2),  step  23). If  pressure  gage  indication  is  between  2500-2550  PSI,  remove  and  repair  lift  cylinder  assembly (para 3-30e). 3-196