M977, M985, and M984E1 Crane Maintenance Instructions (Cont)
17-21. HOIST DRIVE MOTOR CONTROL VALVE REMOVAL/REPAlR/INSTALLATION
Perform steps (7) and (8) if plugs were
Coat threads of two plugs (6) and elbow (5)
with pipe thread sealing compound.
Install two plugs (6) and preformed
packings (7) in housing (3).
Apply hydraulic oil to preformed packings (41
Install preformed packing (4) and elbow (5)
in housing (3).
Install two preformed packings (2) and
fittings (1) in housing (3).
There are two models of control valves.
Model A (Snap-Tite, no longer available as
an assembly) has an SAE #4 brake port. Model B (Dana) has an SAE #6 brake
port. Installation procedures are identical for both. However, if replacing Model A
with Model B, elbow located between hoist motor control valve and brake port hose
must be replaced (step b, substep (3.2)).
Install two preformed packings (1) and control valve (2).
Adhesives, solvents, and sealing compounds can burn easily, can give off harmful
vapors, and are harmful to skin and clothing. To avoid injury or death, keep away
from open fire and use in well-ventilated area. If adhesive, solvent, or sealing
compound gets on skin or clothing, wash immediately with soap and water.
Apply sealing and thread locking compound and install four lockwashers (3) and screws (4).
Follow-on Maintenance. Install hoist hydraulic hoses and tubes (para 17-2).
END OF TASK
17-96 Change 3