5troubleshooting – Trebor 620D Magnum User Manual
Page 23
![background image](/manuals/594911/23/background.png)
MAGNUM 620D PUMP OPERATION / MAINTENANCE MANUAL
PAGE 23
5
TROUBLESHOOTING
Pump Will Not Start, Fails to Operate
Cause:
Solution:
Insufficient air pressure.
Must be minimum 12 psig at pump air hook-up.
Insufficient air volume (low supply
pressure during running).
See Performance Charts (3.1) for requirements. Check
for both regulator and control valve C
v
s >.85 capabilities.
Fluid discharge line blocked.
Downstream valve closed, filter plugged
or other obstruction.
Remove obstruction.
Pilot valve failure.
Inspect and replace pilot valve body and poppet.
Detent failure.
Inspect detent legs for worn or damaged parts.
Bubbles in Fluid Discharge
Cause:
Solution:
Leaking fluid inlet fitting.
Tighten fittings or replace adapter seal.
Leaking main seal.
Tighten heads an additional 15
.
Replace diaphragms, and check head and body grooves
for nicks or scratches.
Pump inlet line pressure reached
saturation point (due to high suction
requirement).
Increase diameter of suction supply line (reduces
restriction).
Reduce output flow.
Ruptured (perforated) diaphragm.
Replace diaphragms.
Check bore caps leaking.
Tighten check bore caps or replace seals.
Fluid Leaks
Cause:
Solution:
Head torque not enough to affect seal.
Remove heads and allow them to sit for 1 hour.
Reassemble with new diaphragms.
Leaking main seal.
Replace diaphragms.
Check head and body seal grooves for nicks and
scratches.
Check bore cap.
Tighten, or remove and replace seal.
Ruptured diaphragm(s) can result in
fluid leaks through air exhaust port and
shuttle valve.
Replace diaphragms and any parts that may have been
damaged by fluid exposure.
Erratic Cycling
Cause:
Solution:
Fluid supply inlet pressure too high.
Adjust check muffler per Section Error! Reference
source not found..
Pilot valve failure.
Inspect and replace pilot valve body and pilot.
Suction line restricted (cavitation).
Reduce fluid restriction
Detent failure.
Inspect and replace spool assembly.
Check ball(s) not seating.
Check O-rings for damage; replace if necessary.
Make sure check balls move freely in sleeves.
Over pressurization of pump discharge.
Reduce discharge pressure by reducing restriction.