Warning, Troubleshooting – Graymills DDP 1' Pump OMI User Manual
Page 14
14
Troubleshooting
WARNING
To reduce the risk of serious injury whenever you are
instructed to relieve pressure, always follow the Pres-
sure Relief Procedure on page 11.
1.
Relieve the pressure before checking or servicing the
equipment.
2.
Check all possible problems and causes before disas-
sembling the pump.
PROBLEM
CAUSE
SOLUTION
Pump cycles at stall or fails to hold
pressure at stall.
Worn check valve balls (301), seats
(201) or o-rings (202).
Replace. See page 17.
Pump will not cycle, or cycles once
and stops.
Air valve is stuck or dirty.
Disassemble and clean air valve. See
pages 15 to 16. Use filtered air.
Check valve ball (301) severely worn
and wedged in seat (201) or manifold
(102 or 103).
Replace ball and seat. See page 17.
Check valve ball (301) is wedged into
seat (201), due to overpressurization.
Install Pressure Relief Valve
(see page 9).
Dispensing valve clogged.
Relieve pressure and clear valve.
Pump operates erratically.
Clogged suction line.
Inspect; clear.
Sticky or leaking balls (301).
Clean or replace. See page 17.
Diaphragm ruptured.
Replace. See pages 18 to 20.
Restricted exhaust.
Remove restriction.
Air bubbles in fluid.
Suction line is loose.
Tighten.
Diaphragm ruptured.
Replace. See pages 18 to 20.
Loose inlet manifold (102), damaged
seal between manifold and seat (201),
damaged o-rings (202).
Tighten manifold bolts (106 or 112) or
replace seats (201) or o-rings (202).
See page 17.
Loose fluid side plate (105).
Tighten or replace (pages 18 to 20).
Damaged o-ring (108).
Replace. See pages 18 to 20.
Fluid in exhaust air.
Diaphragm ruptured.
Replace. See pages 18 to 20.
Loose fluid side plate (105).
Tighten or replace (pages 18 to 20).
Pump exhausts excessive air at stall.
Worn air valve block (7), o-ring (6),
plate (8), pilot block (18), u-cups (10),
or pilot pin o-rings (17).
Repair or replace. See pages 15 to 16.
Worn shaft seals (402).
Replace. See pages 18 to 20.
Pump leaks air externally.
Air valve cover (2) or air valve cover
screws (3) are loose.
Tighten screws. See page 16.
Air valve gasket (4) or air cover gasket
(22) is damaged.
Inspect; replace. See pages 15 to 16
and 21 to 22.
Air cover screws (25) are loose.
Tighten screws. See pages 21 to 22.
Pump leaks fluid externally from ball
check valves.
Loose manifolds (102, 103), damaged
seal between manifold and seat (201),
damaged o-rings (202).
Tighten manifold bolts (106 or 112) or
replace seats (201) or o-rings (202).
See page 17.