MTD 700 Series Professional Shop Manual page 121

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Figure 7.34
Figure 7.35
5. Stator check (full wave rectifiers): See Figure 7.34.
5a. Key OFF, unplug the stator from the regulator/
rectifier.
5b. Check resistance through the stator using a dig-
ital multimeter set to read Ohms.
NOTE: Refer to the engine manufacture for the specified
readings.
• A high reading indicates a fault in the windings.
• A low reading indicates a short in the windings.
• There should be a reading of O.L. (Open Line)
between either lead and the engine block.
NOTE: It is good practice to check the stator cold, and
again when the engine is at operating temperature.
5c. Check the raw output of the stator.
See Figure 7.35.
• Connect a meter set to read Volts A.C. to the out-
put leads of the stator.
• Start the engine and advance the throttle to 3,000
RPM.
• The stator should produce at least 26 Volts A.C. In
some cases, output will be as high as 34 Volts A.C.
6. Interpretation:
• If the stator fails either or both tests, it is likely to be
bad.
• If the stator fails the output test, but passes the
resistance test, there is a possibility that the mag-
nets on the rotor (flywheel) have lost their fields.
This is theoretically possible, but extremely rare in
practice.
• It is necessary to remove the flywheel to test the
magnets. If the magnets inside the flywheel will
draw a steel screwdriver to them, they are good. If
not, the flywheel must be replaced.
Electrical
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