Lull 6K Service Manual User Manual
Page 201
Supply, Pressure, and Return Hydraulics
Service Manual — Models 644B, 6K, 844C, 8K, 1044C, 10K
5-57
Assembly, CRA Assembly
(Ref. Fig. 5-36) The following procedure describes reassembly of the CRA
assembly.
1. Obtain seal kit and new square cut seal. Lubricate each seal, backup
washer, and other internal parts, with hydraulic oil before installing
them.
2. Install new O-ring (Item 19) near head of relief body (Item 18).
3. Install new backup washer (Item 20) and O-ring (Item 21) near middle
of relief body.
4. Install two (2) new backup washers (Item 25) and O-ring (Item 26) on
poppet retainer (Item 24). Make sure O-ring is installed between
backup washers.
5. Install poppet (Item 28) and check spring (Item 27) on poppet retainer
(Item 24). Then install poppet retainer in housing (Item 6).
CAUTION: Care must be taken to avoid damaging O-ring and backup
washers when installing poppet retainer. The poppet retainer
must go into the orifice exactly square and very slowly. It will fit
snug.
6. Install anti-cavitation spring (Item 23) and poppet (Item 22) in poppet
retainer.
7. Install new piston ring (Item 17) on relief poppet (Item 16), O-ring
(Item 13) on piston (Item 12), and O-ring (Item 11) on adjustable relief
cap (Item 10).
8. Install relief poppet, shims (Item 15), spring (Item 14), and piston in
relief body.
9. Install O-ring (Item 11) on adjustable relief cap (Item 10).
10. Install adjustable relief cap on relief body. Torque relief cap to 20 ft-lbs.
11. Install adjustable stem in relief cap.
12. Install jam nut (Item 8) on adjustable stem. Torque jam nut to 15 ft-lbs.
13. Install acorn nut (Item 7) on adjustable stem. Torque nut to 15 ft-lbs.
14. Install relief assembly (Items 7 thru 21) on housing. Torque relief
assembly to 20 ft-lbs.
15. Install new square cut seal (Item 5) in housing.
16. Install positioner housing (Item 4) on housing with four (4) each
bearing washers (Item 3), lockwashers (Item 2), and socket head
capscrews (Item 1). Refer to note made earlier to ensure housing is
installed in same position as when removed. Torque capscrews to
4–6 ft-lbs.