Lull 6K Service Manual - Manual (Page 510)

Frame Tilt and Oscillation
7-8 Service Manual — Models 644B, 6K, 844C, 8K, 1044C, 10K
4. Check surface of each plunger (Item 17) and guide (Item 12) for wear
and damage. Check fit of plunger in guide to make sure no sticking
occurs. Like the spools, a stuck plunger can cause unintentional
operation of a hydraulic circuit.
5. Inspect each spool cavity in the valve body for scratches.
6. Check condition of lever assembly (Item 1), cam (Item 3), pivot pin
(Item 8), springs (Item 19), and flange (Item 9). Replace as necessary.
7. Replace O-rings and seals as necessary. Lubricate O-rings and seals
with clean hydraulic oil before installing them.
Assembly, Frame Tilt Control Valve
1. If ported guides (Item 24) were removed, install new O-rings and apply
non-permanent thread sealant sparingly to bottom threads (nearest
the hex end of guide). Do not use too much sealant as the hydraulic
system may become contaminated. Lubricate O-rings (Items 22 & 23)
with clean hydraulic oil and install ported guides in valve body
(Item 20). Torque guides to 240–260 in-lbs.
2. Install springs (Item 19). Lubricate spool assemblies (Item 18) with
clean hydraulic oil and install.
3. Lubricate O-rings (Item 13) and plungers (Item 17) with clean hydraulic
oil. Insert plungers into guides (Item 12) with circlip (Item 16) on spool-
side of guide. Install guide assemblies (Item 10).
4. Position flange (Item 9) on valve body as previously noted. Secure
flange with four (4) washers (Item 6) and capscrews (Item 5).
5. If rubber boot (Item 2) was previously removed, install boot on lever
assembly, taking care not to damage boot on pin located near bottom
of lever assembly (Item 1). Install new plastic cable tie around top of
boot to help prevent water from entering between lever assembly shaft
and boot. Place cam (Item 3) on lever assembly and install roll pin
(Item 4).
6. Lubricate cam (Item 3) and pivot pin (Item 8) with grease. Position
lever/boot/cam assembly (Items 1–4) in flange with pin on lever aligned
with notch in flange. Install pivot pin and secure with circlips (Item 7).
7. Move lever fully left and right. Make sure plungers (Item 17) do not
stick down. If sticking occurs, the valve must be disassembled and the
problem corrected.
8. Slip rubber boot into position over flange.
9. Install fittings and plugs at previously noted positions. Torque plugs
(Item 21) and fittings (Item 25) to 300–340 in-lbs. Cap all open ports
and fittings.