ARMY TM 5-5420-212-23
MARINE CORPS TM 08676A-23/3
(3)
HYDRAULIC JACK 15T & 20T- RAM WILL NOT LIFT/LOWER (paras. 2-26 and 2-33, 3-9 and 3-10).
a.
Check for worm pump and internal leaks. Check pump plunger seal, pump barrel seal and spring seat on
suction/delivery/release valve.
Replace as necessary.
b.
Check valve seat in bottom of ram for damage/debris.
Clean and replace as necessary.
c.
Check release valve
Clean and replace as necessary
(4)
HYDRAULIC JACK 15T & 20T- EXTERNAL LEAKS
Check for damaged or worn seals, loose screws. Inspect ram packing, body seal, body gasket, filler cap
seal, base plug and ball, suction/delivery/release valve, body screws.
Replace as necessary.
(5)
HYDRAULIC JACK 15T & 20T - EXCESSIVE WEAR ON PUMP.
a.
Check type of fluid.
Only type MIL-L-7870A to be used.
b.
Check quality of fluid in jack.
Deteriorated fluid to be replaced and system flushed out and refilled with MIL-L-7870A.
c.
Check for contaminated fluid.
Contaminated fluid to be replaced and system flushed out and refilled with MIL-L-7870A.
Clean filter.
d.
Check for air pockets in system. Inspect pump plunger seal and pump barrel seal.
Bleed system and replace parts as necessary.
e.
Check for lack of fluid in system.
Fill with MIL-L-7870A only.
f.
Check for dirt in system.
Flush system, clean/replace filter and refill with fresh clean MIL-L-7870A.
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