Approximate Gauge Gauge
Pressure Reading Between Between
at Gauge Pump/Unloader Unloader/Gun-Nozzle-Valve
System in operation system pressure system pressure
(gun open)
System in by-pass 200-300 PSI above 200-300 PSI above
(all guns,valves closed) system pressure system pressure
SERVICING
Disassembly:
1. Disconnect by-pass and inlet plumbing from regulator.
2. Remove regulator from pump.
3. Secure lower body of regulator in a vise with adjusting handle
facing upwards.
4. Remove adjusting cap and unthreading from upper body in a
counterclockwise direction.
5. Remove upper body by unthreading from lower body.
6. Remove upper spring retainer, spring set and conical piston.
NOTICE: Exercise extreme caution to avoid contact and damage
to outside diameter and sharp tip of conical piston.
7. Remove lower body from vise and place on flat surface with
by-pass port facing upwards.
8. Using a tool with the same diameter as that of the conical seat
drive out the conical seat and piston retainer.
NOTICE: Exercise extreme caution to avoid contact and damage
to the inside diameter of the piston retainer as well as the outside
diameter and tapered surfaces of the conical seat.
Note: With the regulator completely disassembled, inspect
sealing area where the conical seat and piston retainer makes
contact within the lower body of the regulator for grooves, pitting
and wear. If damage is found, stop the repair and replace with
new lower body or complete new regulator. If not, proceed with
reassembly.
Reassembly:
1. Place lower regulator body with by-pass port facing
downwards in a vise.
2. Lubricate and install o-ring onto outside diameter of conical
seat. Press conical seat down into lower regulator body with
tapered surface facing upwards.
3. Lubricate and install o-ring onto piston retainer. Press piston
retainer with larger diameter facing downwards.
4. Place conical piston on a flat surface with sharp point facing
upwards. Lubricate and install backup-ring, then o-ring
onto outside diameter of conical piston. Lubricate outside
diameter of conical piston.
5. Press conical piston with sharp point down into piston
retainer.
6. Place upper body with large opening facing up.
7. Drop spring retainer into cap, ensuring spring pilot faces up.
8. Drop in 28 spring washers, alternating direction per exploded
view on the last page.
Note: A small rod such as an ink pen can be used to guide the
washers into the cap to ensure proper orientation is maintained.
9. Invert lower body assembly onto upper body and thread
together.
10. Thread adjusting cap into upper body
11. Re-install regulator onto pump.
12. Reconnect by-pass and inlet plumbing to regulator.
13. Proceed to PRESSURE ADJUSTMENT.
TROUBLESHOOTING
Cycling/Chattering l Too little flow for valve specifications.
l Air in system, poor connections.
l Inlet seals in pump worn.
l O-ring in gun worn.
System will not l Nozzle worn.
build up to pressure l Improper nozzle size for system specs.
l Foreign material trapped in seat.
Pressure drop l Nozzles worn.
l Piston and seat in regulator worn.
l Air in system, poor connections.
l Insufficient flow to pump.
l Filter clogged. Check and clean
regularly.
Pressure spikes l Minimum by-pass of 5% not present.
while in by-pass l Excessive pressure adjustment
made for worn nozzle. REPLACE
NOZZLE. Reset system pressure.
Leakage from l O-ring around piston worn or piston
regulator vent hole retainer scored. Service with o-ring kit.
Read all CAUTIONS and WARNINGS before commencing
service or operation of any high-pressure system
