Blagdon Pump X25 Metallic - Manual (Page 10)

x25fvmdl1sm-rev0411 Page 8
Most problems with the pilot valve can be corrected by replacing the
o-rings. Always grease the spool prior to inserting it into the sleeve. If the
sleeve is removed from the body, reinsertion must be at the chamfered side.
Grease the o-rings to slide the sleeve into the valve body. Securely insert the
retaining ring around the sleeve. When reinserting the pilot valve, push both
plungers (located inside the intermediate bracket) out of the path of the pilot valve spool
ends to avoid damage.
PILOT VALVE ACTUATOR
Bushings for the pilot valve actuators are held in the inner chambers with
retaining rings. An o-ring is behind each bushing. If the plunger has any sideways motion,
check o-rings and bushing for deterioration or wear. The plunger may be removed for
inspection or replacement. First remove the air distribution valve body and the pilot valve
body from the pump. The plungers can be located by looking into the intermediate. It
may be necessary to use a fine piece of wire to pull them out. The bushing can be turned
out through the inner chamber by removing the outer chamber assembly. Replace the
bushings if pins have bent.
WARRANTY:
This unit is guaranteed for a period of five years against defective material and workmanship.
POSSIBLE CAUSES:
A. Air leak in suction line.
B. Excessive suction lift.
C. Flap valve not seating properly.
D. Leakage at joint of suction manifold or elbow flange.
E. Suction line or strainer plugged.
F. Diaphragm ruptured.
POSSIBLE CAUSES:
A. Discharge hose or line plugged, or discharge head requirement
greater than air supply pressure.
(Disconnect discharge line to check.)
B. Spool in air distribution valve not shifting.
(Remove end cap and check spool — must slide freely.)
C. Diaphragm ruptured.
(Air will escape out discharge line in this case.)
D. Blockage in diaphragm chamber preventing movement.
(Shut off air supply and reopen after pressure is relieved.)
POSSIBLE CAUSES:
A. Flap valve not sealing properly in one chamber.
B. Diaphragm failure in one chamber.
C. Air leak at suction manifold joint or elbow flange one side.
PROBLEM
Pump cycles but will not pump.
(Note: higher suction lifts require faster
cycling speed for priming.)
PROBLEM
Pump will not cycle. (Note: Always
disconnect air supply to relieve air
pressure before disassembling any
portion of pump.)
PROBLEM
Uneven discharge flow. (Indicates one
chamber not operating properly.)
TROUBLESHOOTING