Assembly 1

Servicing

Servicing is normally restricted to the replacement of seals, cleaning of ancillary valves and replacement of preset assemblies.

Dismantling

1. Make sure all the blanks are secure in the ports then clean any dirt off the assembly before dismantling.

2. Label all sections and make a note of the order that the components are assembled.

3. Stand the control valve on its end with the outlet section (PVP) (1) uppermost.

4. Remove the nuts (2) and washers (3) from the tie bolts (4) and remove the PVP section. Remove the other sections of the valve, one at a time.

5. Remove and discard the inter-section O-ring seals.

6. Examine the self-locating grooves for burrs, nicks or other damage.

7. Burrs may be removed by careful honing with a very fine grade stone. Any cut damage to a groove requires that section to be replaced.

Assembly

Use new O-rings when assembling the valve, lightly lubricated with clean hydraulic oil.

Before assembly, the section mating surfaces should be cleaned and lightly lubricated with clean hydraulic oil.

1. Assemble the sections onto the tie-bolts in the correct order, as noted during dismantling. Make sure that the identity marks align and the O-ring seals are located in the grooves

Take care when tightening the tie-bolts to avoid distorting the sections and possible binding of the spools and/or seal leakage.

2. Fit the washers and nuts to the tie-bolts and tighten finger tight.

3. Tighten the tie-bolt nuts progressively in rotation and torque load to 25 Nm (18 lbf/ft.). 1 Outlet section (PVP) (26) 2 Nut 3 Washer 4 Tie-bolt