d. Makeup Valves.
(1) General. Makeup valves are provided to
(a) Remove the hydraulic tank from tractor
supply tank oil (directly to the bulldozer cylinder
and remove the tank assembly from bottom plate
lines whenever the line pressure, is less than tank
pressure. This occurs when the bulldozer blade
(b) Remove bolts (4. fig. 4-8) and remove
raises or lowers rapidly. The valves are located in a
makeup valve body (3).
common valve body bolted to the bulldozer control
(c) Remove bolts (1) and (6) and remove
covers (2) and (5).
valve. A spring holds each valve seated during
normal operation. When oil pressure in the
(d) Remove springs (3, fig. 4-9) and valves
bulldozer circuit is reduced, oil in the tank over-
comes the spring, opens a valve and flows into the