Graco ProX7 & ProX9 Manual Do Utilizador

If Motor Diagnostics reveal a damaged motor or if motor brushes are shorter than 1/4 in. (6.4 mm) replace the motor 
using 

Motor Kit, page 28.

1. Unplug power cord and 

Relieve Pressure, page 11.

2. Remove enclosure and disconnect two black motor 

leads to control board (see 

Wiring Diagram, page 

3. Remove motor fan cover by gently prying up on 

retention tabs on sides of motor. Motor shaft should 
spin easily when turning fan. If motor shaft does not 
turn easily, there is a problem with pump, gears, or 
motor (see 

Troubleshooting, page 13).

4. Inspect motor windings for evidence of overheating. 

If windings appear burnt and motor smells, replace 
motor.

5. Use Ohmmeter to measure resistance across two 

black motor leads. Resistance of motor should fall 
within range of 1.5 to 4.5 ohms. If motor falls outside 
resistance range or is open circuit, replace motor.

6. Use Ohmmeter to measure resistance of motor leads 

to motor laminations. If resistance is not open circuit, 
replace motor. 

7. Inspect length of both brushes by looking at brush 

torsion spring. If spring is not bottomed out in slot for 
brush spring, brush length is acceptable. If brushes 
are worn out, replace motor.

Check for electrical continuity in motor armature, windings and brush as follows:

If Motor Diagnostics reveal a damaged motor or if motor brushes are shorter than 1/4 in. (6.4 mm) or if the motor shaft 
cannot turn, replace the motor using 

Motor Kit, page 28.

1.

Relieve Pressure, page 11.

2. Unplug electric cord.

3. Remove enclosure and disconnect motor leads from 

control card.

4. Remove fan brace.

5. Remove four screws and front cover.

6. Remove yoke and guide rods.

7. Remove gear.

Quickly turn motor fan by hand. There should not be 
electrical shorts and fan should coast two or three 
revolutions before stopping. If fan does not spin freely, 
armature is shorted. Replace motor using 

Motor Kit, 

page 28.

1. Connect red and black motor leads together with test 

lead. 

2. Turn motor fan by hand, about two revolutions per 

second.

3. If there is an uneven resistance or no resistance, 

replace motor using 

Motor Kit, page 28.