Changing the Diaphragm and Valves (Optional)
6
The Bosworth Company
Doc M-09-31-111516
When replacing the diaphragm it is best to remove and repair only one pump body before a
Ʃ
emp
Ɵ
ng to remove
the other body. Close a
Ʃ
en
Ɵ
on should be paid to the orienta
Ɵ
on of various parts. The use of witness marks may
be helpful during the reassembly.
1. Disconnect the power.
2. Place the pump assembly with the motor in a
ver
Ɵ
cal posi
Ɵ
on.
3. Remove the manifolds by loosening the hose
clamps holding the manifold to the pump
fl
anges.
4. Remove the 10 screws holding the pump body to
the housing.
(Figure 8)
5. Remove the pump body to expose the diaphragm
screw a
Ʃ
aching the plas
Ɵ
c “bu
Ʃ
on” (a plas
Ɵ
c support
plate) to the diaphragm.
6. Pull the diaphragm out to its maximum travel. Re-
move the slo
Ʃ
ed head screw, washer, bu
Ʃ
on and dia-
phragm from the plas
Ɵ
c clevis.
(Figure 9)
Note: If you plan to change the valves, do so now. Other-
wise, go to step 10.
7. Using
a
narrow
fl
at-
Ɵ
pped screw driver, push on the
stem (center) of the umbrella valve. Con
Ɵ
nue pushing
the valve from the pump.
(Figure 10)
8. Push the new umbrella valve (stem end
fi
rst) toward
the
fl
at side of the valve stop. Ensure the valve is seat-
ed in the center hole of the valve stop. Using needle-
nose pliers, pull on the valve stem from the other side
un
Ɵ
l it snaps securely into place.
9. Repeat steps 7 and 8 to change the other umbrella
valve.
Removing the old Diaphragm;
Quick Valve Change
Remove pump body from housing.
Figure 8
Remove diaphragm.
Figure 9
Push umbrella valve out of valve stop.
Figure 10
