Airstream INTERNATIONAL TRAILER Owner's Manual page 74

AIRSTREAM INTERNATIONAL TRAILER OWNERS MANUAL
Pump Repair

Screws (A) hold the entire pump head assembly to the
motor.

Screws (B) hold the pump head face to the pump head
main body. Screws (C) hold the switch assembly to the
front of the pump head.

Screws (A) would be removed to correct a problem in
the "drive train" between the motor and pump head. Screws (A) and (B) would be removed to
correct a problem in the pump head valves or pumping chambers.

Screws (C) would be removed to correct a problem in the automatic switch or check valve.
PUMP HEAD REPAIR
Motor and drive train.
Rarely does a problem occur in this area of the pump head. If a part does fail, it is quite easily replaced. Just
be certain to follow closely the sequence of parts as shown in the figure. Also be careful to align the flat
surface in the drive adapter with the flat surface on the motor shaft.
LUBRICATION
If the lubricant appears dried out it should be wiped off the bearing assemblies. A small amount of
automotive wheel bearing grease should be applied to both sides of each bearing.
FAILURE TO PRIME
Failure to prime can be caused by the presence of some foreign matter lodged in the valve preventing it
from seating. To correct, remove any such foreign bodies.
CAUTION
: Do not remove the stainless steel screens. These filter screens should be cleaned
without removing them from the plastic housing.
PUMP CHAMBER REPAIR
Replacement of broken piston.
To remove a piston, back out the screw holding the defective piston.
Now lift the corner of the diaphragm and remove the broken piston. Insert the new piston through the
diaphragm and slide the retaining ring on. Rotate the piston until it drops into place in the drive plate.
Replace the screw and tighten until snug.
CAUTION
: Do not attempt to re-use a piston once it has been removed. The plastic stem, if used
a second time, may not hold securely. The second thread path removes additional material and there
is then no real bite.
REPLACE A DIAPHRAGM
To replace a diaphragm follow the procedure used in removing the pistons. After removing the three
pistons the diaphragm is loose and easily removed.

Screws (A) hold the piston.

Screws (B) hold the drive mechanism and should not be removed when replacing piston.
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