Motor Replacement - Graco ultra 750 Instruction Manual

WARNING
Before doing this procedure, follow the Pressure
Relief Procedure Warning on page 24 to reduce
the risk of a fluid injection injury , splashing in the
eyes or in the skin, injury from moving parts or elec-
tric shock. Unplug the sprayer!
Refer to FIg 35–1 unless otherwise instructed.
1. Remove the motor shield (56).
2. Remove the pressure control cover (63). Disconnect
the four motor leads.
3. Loosen the conduit connector nut (345) at the pres-
sure control (75).
4. Swing the conduit (1) away from the pressure control
elbow (31).
5. Remove the conduit seal (29) from around the con-
duit elbow coming into the control box. Pull the motor
leads through the elbow, one at a time.
CAUTION
Always pull the motor leads one at a time to avoid
loosening the terminals, which could result in a bad
connection and poor sprayer performance.
6. Loosen the connector nut (31) at the motor and pull
the conduit (1) away from the motor . Pull the leads
through the conduit, one at a time.
7. Unscrew the connector elbow from the motor.
8. Pull the wires through the elbow, one at a time.
9. Remove the front cover and screws (49, 24).
10. Remove the two screws (26) and washers (20) from
the recess of the drive housing,
11. Remove the two screws (13) and washers (20) from
the lower rear of the motor front end bell (73b),
12. Remove the two screws (16) and washers (20) from
the upper rear of the motor front end bell (R).
13. Use a plastic mallet to gently tap the displacement
pump (76) from the rear to loosen the drive housing
(67) from the front end bell (R). Pull the drive housing
away from the end bell.
307–786

MOTOR REPLACEMENT

DO NOT allow the gear cluster (51) to fall when re-
moving the drive housing (67). It is easily damaged
if dropped. The cluster may stay engaged in either
the front end bell or the drive housing.
DO NOT lose the thrust balls (9) located at each
end of the gear cluster (51) or allow them to fall be-
tween gears. The ball, which is heavily covered with
grease, usually stays in the gear recesses, but
could be dislodged. If caught between gears and
not removed, the balls will seriously damage the
drive housing. If the balls are not in place, the bear-
ings will wear prematurely.
14. While supporting the motor to keep the sprayer from
15. Place the new motor on the frame and align the
16. Liberally grease the gear cluster (51) and pinion gear
17. Place the bronze–colored washer (67b) and THEN
18. Align the gears and push the drive housing (67)
19. Starting at Step 12 and working backwards, continue
NOTE: Use a turning motion on the conduit (1) when
20. Install the conduit seal (29) around the wires in the
21. Install the motor shield and pressure control cover.
CAUTION
tipping, remove the four screws (8), washers (87),
lockwashers (11) and nuts (10) holding the motor to
the frame. Lift off the motor.
frame mounting holes. Install the screws (8),
washers (87), lockwashers (11) and nuts (10), tightly.
(B) and pack all bearings in the motor front end bell.
Check to be sure the thrust balls (9) are in place.
the silver–colored washer (67a) on the shaft protrud-
ing from the big gear in the drive housing (67).
straight onto the front end bell (R) and locating pins.
to reassemble the sprayer.
feeding wires through it.
conduit elbow (345) at the pressure control to keep
contaminants from entering the motor conduit. See
the Detail in FIg 35–1.