Lull 944E-42 Service Manual User Manual download pdf (Page 313)

Model 644E-42/944E-42 Rev. 6/04

Hydraulic System

If the pump is not

functioning properly

Inspect the check valve in the

cooler hydraulic line.

If the cooler is not cooling

the oil, check that the

radiator and cooler are not

clogged or obstructed.

Replace check valve.

Refer to Section 9.14.4, “Dual

Hydraulic Oil Temperature

Clean radiator and cooler.

Repair/replace suction line.

Check suction line from

reservoir to the pump.

When checking pressures in

circuits, refer to Section 8.7,

“Hydraulic System Testing,” for

correct pressure readings.

Before troubleshooting any

hydraulic circuit, ALWAYS

begin by checking the

1. Hydraulic oil level in the

2. All hoses, tubes, fittings

for leaks, kinks,

interference, etc.

3. Air in the lines

Repair/replace pump.

Lull 944E-42 Service Manual User Manual Page 313