Commutator Brush Inspection - Jet JWSS-22B Operating Instructions Manual

Figure 29

11.4 Commutator brush inspection

To maintain motor efficiency, inspect the two carbon
brushes every two months, or more frequently if saw
is heavily used. Stalling or loss of power may be a
symptom of worn carbon brushes. If one brush is
worn out, replace both at the same time.
Continued use of a damaged or
worn brush may result in damage to motor
armature.
1. Unplug saw from power source.
2. Unscrew and remove cap with flat blade
screwdriver. See Figure 30.
3. Gently pry up an edge of the brass clip, until the
spring causes it to disengage from hole. (Notice
orientation of brush as you remove it; it should
be inserted in the same manner; curvature of
brush will match curvature of motor.)
4. Pull out brush and inspect. Brush should be
replaced if any of the following are discovered:
•
Brush has worn to about 1/2-inch long.
•
Signs of crumbling, burning or breaking.
•
End of brush is rough or pitted.
•
Abnormal coloration of spring
•
Broken lead in spring
•
Collapsed spring
5. Install new brush (or reinstall current brush) and
gently press it all the way into hole until the
brass clip is secured.
6. Install cap.
7. Repeat for other brush.
NOTE: It is recommended that saw be run without
load for several minutes to seat new brushes.
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Figure 30