G57 DISASSEMBLY PROCEDURE
First, remove all gas (air in) lines and suction/discharge fittings
from me pump. This is accomplished by using a flat-bladed
screwdriver to slide the retaining clips away from the gas (air in)
and suction/discharge fittings and pulling the fittings away from
the pump body. Now remove the muffler by sliding the retaining
clip away from the muffler base and pulling the muffler out of the
pump body.
UsIng a Phillips screw driver remove the seven (7) screws from the
front end cap followed by the (7) screws from the rear end cap.
With the front end cap facing up and the rear end cap facing down
on the workbench, position a flat bladed screw driver into the slot
located above the muffler port and just below the pad marked
Air/C02 and lift off the front end cap. The rear end cap can be
removed by placing the flat bladed screwdriver under the fully
opened port retaining clip and lifting off.
Note the position of the suction and discharge valves before
removing them from the pump body. The first diaphragm is
removed from the pump shaft by unscrewing in a counter clock-
wise direction. The second diaphragm is removed by placing the
flat tip of a screwdriver the exposed slot at the end of the pump
shaft and unscrewing me diaphragm from the shaft. To remove the
flange housing, place the tip of the flat bladed screw driver into the
air bleed hole on the lower side of the flange housing and lift up
the lower end separating the flange housing from the pump body.
The slide valve assembly and pump shaft can be removed by sim-
ply pulling them from the pump body. The pump shaft then can be
removed from the slide valve yoke assembly.
REASSEMBLE PROCEDURE
Assemble the slide valve and pump shaft with the yoke placed
between the (2) bumpers on the pump shaft. Install the slide
valve/pump shaft assembly into the pump body making sure the
O-rings in the slide valve are in place. To install the flange housing,
prelube the o-ring with Parker Super “O” Lube and install on flange
housing and place housing over the pump body aligning the flange
housing with the pump body ribs pressing it into place.
Install the first diaphragm and O-ring on to the pump shaft by
threading on to shaft using a flat blade screwdriver to hold the
pump shaft until the diaphragm is tight. Install the second
diaphragm and O-ring on to the pump shaft turning clockwise until
tight.
Install the suction valves with springs facing into the pump body
and the discharge valves with the springs facing out. See arrows
on pump rear end cap below suction and discharge ports.
Install the port retainer clips (large) into the pump end cap
(mounting base) and install the seven (7) Phillips screws into pump
body and cross tighten until snug and then cross torque to 22-24
inch pounds. Install port retaining clips (small) into the pump body,
tabs facing out, position the front end cap and install the seven (7)
Phillips screws into pump body and cross tighten until snug and
then cross torque to 22-24 inch pounds.
Install the muffler in the center port by pushing it in and sliding the
retainer clip into place. Install the suction and discharge ports and
the (air in) port fitting and slide the retainer clips in place. Check
for leaks.
2B
2A
5
4
3A
6
3A
4
5
7
1A
1A
6
6
2B
2A
Key
Part No.
Description
Qty
1A 20740-050A Kit, Check Valve, Assy., Santo
®
, Hastelloy
4
1B 20740-020A Kit, Check Valve. Assy., Viton
®
, Hastelloy
4
2A 20730-000A
Kit, Diaphragm, Santo,&, w/“O” rings
2
2B
21000-209
Kit, Diaphragm, Viton
®
2
3A
20751-000A Kit, Shaft & Slide Valve Assy. (Santo
®
)
2
3B
20751-002A
Kit, Shaft & Slide Valve Assy. (Viton
®
)
2
4
20896-000A Kit, Flange & Housing Assy. w/“O” Ring
2
5
20753-000A Kit End Caps
2
Key
Part No.
Description
Qty
6
20793-100A Kit Hardware - Includes
Screws #10x1.5” Hi Low
14
Retainer Clip Small
2
Retainer Clip Large
2
Exhaust Port
1
Exhaust Muffler
1
7
20132-000 Kit,
Grommets
2
MODEL G57 SERIES EXPLODED VIEW
