Service And Repair
Replacing the Air Purge Screw
45
extra care to distinguish each one before replacing them in the extractable. Lubricate each O-ring with
petroleum jelly and then install them in their assigned grooves in the extractable (see Figure 29 on page 33).
29. Reinstall the extractable unit into the manifold and tank. Torque the extractable lock-down nuts in an alternating
pattern to 50 ft-lbs (68 N•m).
Remove the springs around the lock-down studs and replace with the springs from the kit.
30. Turn the air purge screw 2 - 3 turns counterclockwise (see Figure 31).
The air purge screw is retained by a hitch pin to limit travel. Do not attempt to rotate
beyond 3 turns.
31. Turn the pump on and let it run for about 2 minutes to purge air from the manifold’s hydraulic cavities. While
the pump is still running, turn the air purge screw clockwise until it is completely closed.
32. If applicable, open the ball valve down line from the pump.
Replacing the Air Purge Screw
Disconnect, lock out, and tag power at the panel before servicing the
pump.
When servicing equipment, use non-sparking tools and use caution when removing or install-
ing equipment to avoid generating a spark.
Kits Required:
• Air Purge Screw Kit (P/N 410484-001)
• Hardware/Seal Kit (P/N 410154-001)
Special tool required: T-handle 1/4’’ hex drive
Procedure:
1.
If a ball valve is installed down line from the pump, close it.
2.
Remove and save the protective plug in the top of the check valve housing and turn the service screw
clockwise (see Figure 38). As the screw approaches its bottom position, you will hear the system
depressurizing. Continue turning the screw until it can go no further. When the screw is all the way down,
backoff the screw 4 turns to lift the check valve and let the fuel drain out of the manifold’s hydraulic cavities.
3.
Unscrew the check valve housing. Notice that the check valve and spring are still attached to the service
screw. Remove and discard the housing O-ring (see Figure 30 on page 35). Set the housing/check valve
assembly aside.
4.
Remove the 2’’ NPT plug, LLD transducer, or MLLD from the line leak detector port in the manifold. Remove
the O-ring from the device and discard.
5.
Locate the air purge screw on the top of the manifold (Figure 38).
6.
The air purge screw has a hitch pin that is set in the horizontal position to limit travel of the screw (see
Figure 39).
7.
Accessing the the hitch pin through the check valve port, use your forefinger to push the pin all the way in as
far as you can. As you unscrew the screw, the pin will be forced down into the vertical position as it contacts
the surface of the manifold’s cavity.
NOTICE
WARNING
OFF
WARNING
