SERVICING THE VALVES
1851/1851K AND 1861/1861K
Disassembly for Discharge Valves
NOTE: Both the standard and the “K” versions are serviced
in the same manner.
1. To service the Discharge Valve Assemblies, it is necessary to
remove the Discharge Manifold.
2. Using an hex wrench, remove the M10 Nuts, Lockwashers
and Flat Washers from the Discharge Manifold.
3. Insert two M8x114 metric threaded bolts into the upper right
and lower left servicing holes on the Discharge Manifold face.
Thread in bolt until it makes contact with Valve Block
Manifold (VBM). Continue threading until manifolds begin to
separate.
NOTE: The Valve Assemblies may stay with either the
VBM or the Discharge Manifold.
4. If Valve Assemblies and Adapters stay in the Discharge
Manifold, remove the exposed O-Rings. Insert two screw-
drivers on opposite sides of the Valve Adapter and pry from
the valve chamber.
CAUTION: Exercise caution as the screwdrivers may
score o-ring sealing area.
5. If the Valve Assemblies and Adapters stay in the VBM, grasp
Spring Retainer tabs and pull assemblies from valve chambers.
6. To separate Valve Assemblies, insert screwdriver into Spring
Retainer and press the backside of Valve until Seat separates
from the Spring Retainer. Each assembly consists of a Spring
Retainer, Spring, Valve, Seat, O-Ring and Back-up-Ring.
7. To remove the Seat from Valve Adapter, insert a reverse pliers
through Seat opening and gently pull out.
CAUTION: Exercise caution as the reverse pliers may
score sealing area.
Disassembly for Inlet Valves
NOTE: Both the standard and the “K” versions are serviced
in the same manner.
1. To service the Inlet Valve Assemblies, it is necessary to re-
move both the Discharge Manifold and the VBM. Follow the
disassembly procedure steps 2 and 3, found under
Disassembly for Discharge Valves.
2. Using an allen wrench, remove the Hex Socket Head Screws
(HSH) from the VBM.
3. Insert two M8x114 metric threaded bolts into the right and left
servicing holes on the VBM face. Thread in bolt until it makes
contact with Inlet Manifold. Continue threading until manifolds
begin to separate. Support underside of VBM to avoid possi-
ble damage to ceramic plungers or plunger rods.
NOTE: The Valve Assemblies may stay with either the
Inlet Manifold or the VBM.
4. If the Valve Assemblies and Adapters stay in the VBM,
remove the exposed O-Rings. Insert two screwdrivers on
opposite sides of the Valve Adapter and pry from the valve
chamber.
CAUTION: Exercise caution as the screwdrivers may
score o-ring sealing area.
5. If the Valve Assemblies and Adapters stay in the Inlet
Manifold, then grasp Spring Retainer tabs and pull
assemblies from valve chambers.
6. To separate Valve Assemblies, inset screwdriver into Spring
Retainer and press the backside of Valve until Seat separates
from the Spring Retainer. Each assembly consists of a Spring
Retainer, Spring, Valve, Seat, O-Ring and Back-up-Ring.
7. To remove Seat from Valve Adapter, insert a reverse pliers
through Seat opening and gently pull out.
CAUTION: Exercise caution as the reverse pliers may
score sealing area.
Removal of Discharge Valve Assembly from
Discharge Manifold
Removal of Inlet Valve Assembly from Valve Block
Manifold
Complete Inlet/Discharge Valve Assembly
CAUTION: Before commencing with service, shut off drive (electric motor, gas or diesel engine) and turn off water supply to
pump. Relieve all discharge line pressure by triggering gun or opening valve in discharge line.
After servicing is completed, turn on water supply to pump, start drive, reset pressure regulating device and secondary valve, read
system pressure on the gauge at the pump head. Check for any leaks, vibration or pressure fluctuations and resume operation.
