TESTING - TM-10-3930-607-150189

HYDRAULIC

obtained, hold screw and tighten jam nut. Install and

tighten acorn nut.

5. Remove the gauge and screw the plug into the

test port.

H. TESTING

1. Operate the spool farthest from the relief valve

to a power position and hold against the relief valve.

Check all external port connections and seals for

possible leakage.

2. Spool Operation

Operate each spool on the valve to its power position.

Spools should move from the power position to neutral

without any hesitancy.

3. Check Valve Leakage Test

Figure 12.

Operate each spool in its power position under load,

B. REMOVAL

until about half the stroke of the cylinder is reached.

Return the spool to neutral position and again apply load

1. Drain the oil from the tank by removing the

to cylinder. There should be no cylinder drop when the

drain plug located in the bottom of the tank toward the

load is again applied. With the cylinder port still under

rear.

load, stop pump flow to the control valve by either

turning off the test stand pump motor or the vehicle

engine, and carefully move the valve spool from the

2. Disconnect all lines and hoses. Cap or plug all

neutral to the power position. In the power position the

openings to prevent the entrance of foreign material.

load should remain stationary.

If load does not remain stationary, the check valves

3. Remove the battery and battery tray.

should be repaired.

4. Remove the tank mounting bolts and lift the

OIL TANK

tank from the truck.

A. GENERAL

C. CLEANING AND INSPECTION

The hydraulic oil tank is of welded steel construction,

bolted into the right hand frame channel, (Fig, 12) The

1. With the filter removed, inspect the tank for

tank is equipped with a fill pipe with breather cap and

foreign matter.

screen strainer, a bayonet gauge, full-flow filter, drain

plug and internal baffles.

2. Steam clean the tank and dry thoroughly.

3. Inspect for leaks.

NOTE:

After welding the tank, clean welds

completely and remove scale, slag or

any other foreign material from the

inside of the tank.

B-153