Magnum 261800, Repair And Parts Manual, Page: 25 / 52

Advanced Troubleshooting
312004B 25
General Problem: Low or Fluctuating Output
Specific Problem Cause Solution
Pump cycles, but output is low or
surging. See Basic Troubleshooting ,
page 17.
Worn or obstructed pump valves. Check for worn pump valves as follows:
Prime sprayer with paint.
Trigger spray gun momentarily.
When spray gun trigger is released pump should cycle
momentarily and stop.
If pump continues to cycle, pump valves may be worn or
obstructed.
Pump Service , page 31.
SR7, ProX7 and ProX9 -
Prime/Spray valve is leaking. Check Prime/Spray valve for debris trapped on seat and
for worn parts. Torque to 130-180 in-lb (15.8-18.1 N•m).
Replace if parts are worn using
AllControl
Prime/Spray Valve Kit , page 28.
Voltage from electrical outlet is too
low. Low voltages reduce sprayer
performance. Check voltage of outlet. Meter must read 85 to 130V
AC.
Reset building circuit breaker or replace building fuse.
Repair electrical outlet or try another outlet.
Extension cord is too long or not
heavy enough gauge. Replace extension cord.
Grounding and Electrical Requirements , page 5.
Leads from motor or pressure
switch to control board are
damaged, loose, pinched, or
overheated. Be sure terminals are centered and firmly connected.
Inspect for pinched wiring and wiring insulation and
terminals for signs of overheating. Replace any loose
terminals or damaged wiring. Securely reconnect
terminals.
Motor brushes are worn. Check length of BOTH brushes (brushes do not wear
evenly on both sides of the motor). Brush length must
be 0.25 in. (6.4mm). If brushes are worn replace motor
using
Motor Kit, page 28.
Motor brush springs are broken. If springs are broken replace motor using Motor Kit ,
page 28.
Motor brushes are binding in brush
holders. Clean brush holders. Remove carbon dust with small
cleaning brush.
Motor stops before sprayer
reaches correct pressure (stall
pressure is too low). Replace pressure control using Pressure Control
Switch Kit , page 28.
Motor armature shorted. Check for shorts using armature tester (growler) or
perform spin test,
Motor Diagnostics , page 30. If
shorts are evident, replace motor using Motor Kit , page
28.