(1) Install tile petcock (8) on the hydraulic oil tank body (3). Tighten the petcock securely.
(2) Position the hydraulic oil tank (3) on its mounting studs and install the mounting lockwashers (4) and nuts
(5). Tighten tile nuts securely.
(3) Install the drain plug (7) on the bottom of the hydraulic oil tank body (3). Tighten the drain plug securely.
(4) Connect the filler hose (9) with the hydraulic oil tank (3) and tighten the hose clamp (1).
(5) Connect the tank to valve hose (2) with the hydraulic oil tank (3) and tighten the hose clamp (1).
(6) Connect the tank to pump hose (6) with the hydraulic oil tank (3) and tighten the hose clamp.
(7) Check to see that all hose connections are tight and secure.
(8) Fill the hydraulic system (c above) and check the oil tank and hose connections for leaks.
Hydraulic Operating Valve
a. General. The hydraulic operating valve consists of the operating valve (fig. 69) and the regulator valve (fig. 70).
The operating valve (fig. 69) controls the flow of hydraulic oil to the steering cylinder for the right or left turn of the steering
roll. The regulator valve (fig. 70) reduces the pressure to a free-flowing circulation of hydraulic oil when the valve is closed.
It is also used to adjust the working pressure of the operating valve.
(1) Turn the spring cover (10) counterclockwise and unscrew it from the spring adjusting screw (7).
(2) Loosen the locknut (9).
(3) Turn the spring adjusting screw (7) clockwise to increase pressure.
(4) Turn the spring adjusting screw (7) counterclockwise to decrease pressure.
(5) The operating valve must be adjusted for a positive steering action. Excessive pressure will make the
steering action jerky.
(6) The recommended hydraulic system working pressure is from 300 to 350 pounds per square inch.
(7) After the proper adjustment is reached, tighten the locknut (9) securely.
c. Operating Valve Removal and Disassembly.
(2) Disconnect and tag all hydraulic lines leading from the operating valve.