Fnr, Nfpe, And Nfph Controls (Bolt-On Valves) - Danfoss Series 42 Service Manual

Service Manual
Minor Repair

FNR, NFPE, and NFPH Controls (bolt-on valves)

Series 42 Axial Piston Closed Circuit Pumps
The FNR, NFPE, and NFPH are non-feedback type controls. The FNR and NFPE controls consist of external,
solenoid-actuated spool valves mounted on the pump housing. The pump receives hydraulic input for
NFPH through ports on the pump's control surface (9/16–18 SAE O-ring boss port). These ports connect
directly to the servo piston.
You may remove the FNR and NFPE controls to clean the ports and replace the O-rings, however, the
controls are not serviceable. The gasket (E074) contains control orifices. Orifice plugs for NFPH pumps are
beneath the servo covers.
FNR and NFPE assembly (bolt-on valves)
D004
D004A
E074 E074
Removal of FNR and NFPE modules (bolt-on valves)
1. Clean the pump and control housings.
2. Remove the four (4) screws (D081) retaining the module to the housing, and remove the module
(D004) from the pump housing.
3. Remove and discard the four O-rings (D004A). Examine the ports for cleanliness.
520L0638 • Rev 0300 • July 2015
D081
4 mm
7 N•m
[5 lbf•ft]
41/51cc
Frame Size
P108 100E
51