JLG 1850SJ Service Manual - Manual (Page 254)

SECTION 5 - BASIC HYDRAULIC INFORMATION & HYDRAULIC SCHEMATICS
5-84 – JLG Lift – 3121619
trol spring are correctly located in the grooves near the end of
the feedback lever arms.
High Pressure Relief Valve Adjustments
1. Remove relief valve cover from pump (ref. item 1).
2. Loosen jam screw (ref. item 2).
3. Holding spring loading nut (ref. item 4) rotate valve
spindle (ref. item 3). For high range relief valve, one turn
equals approximately 630 psi (44 bar). For low range
relief valve, one turn equals approximately 377 psi (26
bar).
4. After adjustment is completed torque jam screw (ref.
item 4) to 5 ft.lb. (7 Nm).
5. Install relief valve assembly into pump, reinstall cover
(ref. item 1) to proper torque.
Removal and inspection of charge pump
Before removing cap screws, mark the position of the charge
pump housing and separator plate in relation to the port
block.
Loosen screws with metric allen wrench.
Remove charge pump housing and inspect for wear or dam-
age to gear set and 0-ring seals. Grease 0-rings prior to reas-
Table 5-1. Torque Specs for Relief Valves into Port Block
Pump Size Wrench Size Torque
28 32 mm 66 ft.lb. (90 Nm)
Pump Size Allen Wrench
28 8 mm