Graymills DDP .375' Pump OMI - Manual (Page 12)

12
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
The pump will not cycle, or cycles
once and stops. The air valve is stuck or dirty. Turn the reset shaft (21).
Disassemble and clean the air valve.
See pages 18, 19.
Use filtered air.
The detent link (22) is worn or
broken. Replace the detent link (22) and ball
(8). See pages 18, 19.
The springs (3, 6) and/or valve cup (5)
and plate (13) are broken or damaged. Replace these parts.
See pages 18, 19.
The pump cycles at stall or fails to
hold pressure at stall. The check valves or o-rings (108) are
leaking. Replace these parts.
See page 21.
The check balls (301) or seat (201) are
worn. Replace these parts.
See page 21.
The check ball (301) is wedged in the
seat (201). Replace the ball.
See page 21.
There is excessive air leakage from the
exhaust port. The air valve cup (5) or plate (13) is
worn. Replace these parts.
See pages 18, 19.
The shaft seals (30}) are worn. Replace the seals.
See page 23.
The pump operates erratically. The suction line is clogged. Inspect; clear the line.
The check valve balls (301) are stick-
ing or leaking. Clean or replace the balls.
See page 21.
The diaphragm (401) is ruptured. Replace the diaphragm.
See page 23.