9. After adjustment, torque the lock nut (L024) to 20 N·m [15 lbf·ft].
C
Caution
Do not over torque.
10. Shut down the prime mover.
11. Remove gauges and replace plugs.
Engaging the Bypass Function
It is possible to damage the drive motor(s) by operating in bypass mode without charge pressure.
Move the vehicle/machine at a speed not more than 20% of maximum for a duration not exceeding 3
minutes.
Use this procedure to bypass the pump to allow moving the vehicle/machine short distances when you
cannot start the prime mover.
Engaging the Bypass Function
L150
P106 649E
1. To open the HPRVs (L150), rotate three revolutions counterclockwise using a hex wrench.
C
Caution
Do not rotate more than 3 revolutions, leakage will result.
2. Rotate them clockwise until seated to close the HPRVs.
See the following table for torque values:
HPRV Wrench Size and Torque Value
Frame size
Wrench size
Torque
045—100
22 mm
70 N•m [52 lbf•ft]
115—280
30 mm
110 N•m [81 lbf•ft]
If machine is towable with HPRVs opened three turns and if wheels are locked (not towable) with HPRV
valves closed, bypass function is working correctly.
Displacement Limiter Adjustment for Single Pumps
If your pump has displacement limiters, you will find them on either servo cover. You can limit forward
and reverse displacement independently.
Displacement limiters are not pre-set by the factory. We install them as far as possible without contacting
the servo piston. Limiting displacement requires clockwise adjustment of the limiting screw.
C
Caution
Before adjusting the displacement limiter, mark the position of the servo cylinder. Be sure the servo
cylinder does not turn when setting the displacement limiter locknut.
Service Manual
H1P 069—H1P 280 Axial Piston Single Pumps
Adjustments
©
Danfoss | January 2021
AX152886482551en-000601 | 37