jcb JS200 Service Manual page 295

Hydraulics
Section E Section E
34 - 2 Port Relief Valve JS200/JS240 34 - 2
Dismantling
Remove the plug 2 and disassemble the sleeve 3, main poppet 4, piston 5 and springs 7, 8.
Loosen the adjuster nut 10 and take out the pilot poppet 6 and spring 9.
Cleaning, Inspection
Clean all the parts with clean oil and dry with compressed air. Inspect each part.
1. Check that there are no defects on the seat surface of each poppet and sleeve end and that the contact surface is even.
2. Check that the main poppet 4 and sleeve 3 slide smoothly. Also check there are no scratches on the main poppet outer
periphery and sleeve inner surface.
3. Check that the springs are not broken, deformed or worn.
4. Check that there is no foreign matter clogging the piston 5 hole. The end seat contact surface should be even.
5. Check that the 'O'-ring and backup rings are not worn or deformed.
If a small defect is found in the above inspection, remove it by lapping.
If an abnormal part is found, replace the relief valve assembly.
Assembly
Install the 'O'-ring 16 and backup ring 17 (2 pcs) to the main poppet 4, assemble the piston 5 and insert into the sleeve 3.
After attaching 'O'-ring 12, backup ring 13 (2 pcs) and 'O'-ring 14 to the plug 2, assemble the sleeve 7, 8 mentioned above.
Tighten cap 1. (Torque 78~88 Nm) (57.84-65.07 lb/ft).
Insert the pilot poppet 6 and spring 9 into the plug 2 and temporarily assemble the adjuster nut 10 and 'O'-ring 11.
Attach 'O'-ring 14 to the cap 1 and assemble into the valve housing. Adjust pressure according to its application, see "Pressure
Testing".
Do not reuse 'O'-rings and backup rings. Replace with new parts.
9803/6400 Issue 1