Filter
Top Products
Return to Section TOC Return to Section TOC Return to Section TOC Return to Section TOC
Return to Master TOC Return to Master TOC Return to Master TOC Return to Master TOC
TROUBLESHOOTING & REPAIR
F-24 F-24
RANGER 250
ROTOR RESISTANCE TEST (continued)
FIGURE F.7 – ROTOR BRUSH LEADS
SLIP RINGS
BRUSHES
LEADS
201
5H
+
-
LEADS
200A
200
TEST PROCEDURE
1. Turn the engine off.
2. Perform the Case Cover Removal proce-
dure.
3. Locate and label the four leads from the rotor
brush holder assembly. See Figure F.7.
Using the needle nose pliers, remove the
leads. See Figure F.7. This will electrically
isolate the rotor windings.
4. Using the ohmmeter, check the rotor winding
resistance across the slip rings. See Figure
F.7. Normal resistance is approximately 4.7
ohms.
5. Measure the resistance to ground. Place
one meter probe on either of the slip rings.
Place the other probe on any good unpaint-
ed ground. The resistance should be very
high, at least 500,000 ohms.
6. If the test does not meet the resistance spec-
ifications, then the rotor may be faulty.
Replace.
7. Connect the leads previously removed from
the brush assembly. Make sure the leads
are connected to the proper brushes. See
the Wiring Diagram.
8. If finished testing, perform the Case Cover
Replacement procedure.