Pto Electric Clutch - Toro Groundsmaster 3280-D Service Manual

PTO Electric Clutch

Testing the PTO Electric Clutch
Groundsmaster ® 3280-D/3320
05138SL Rev B
An electric clutch is used to engage the PTO. The electric clutch is mounted on
the engine crankshaft and engages when current is applied to the clutch. The
clutch also incorporates a magnetic brake to stop clutch rotation when the clutch
is de-energized.
1. Park the machine on a level surface, lower the cutting deck, set the parking
brake, shut off the engine, and remove the key from the key switch.
2. Unlatch the hood and raise it.
g227535
1. Electrical connector
2. PTO clutch
3. Locate the PTO electric clutch on the engine crankshaft
4. Unplug the clutch electrical connector from the machine wire harness.
Note: For accurate clutch resistance measuring, the clutch should be at
approximately 21°C (70°F).
Note: Before taking small resistance readings with a digital multimeter, short
the multimeter test leads together. The meter displays a small resistance
value (usually 0.5 ohms or less). This resistance is because of the internal
resistance of the multimeter and test leads. Subtract this value from the
measured value of the component that you are testing.
5. Use a multimeter (ohms setting), check the clutch coil resistance between
the 2 terminals of the clutch electrical connector. The coil resistance should
be approximately 3.0 ohms. Additionally, check that there is no continuity
between either of the clutch wire connector terminals and the clutch frame.
6. Use the access slots in the clutch cover, measure the gap between the clutch
rotor and the armature
at all the 3 access slots. If gap is incorrect, loosen or tighten the 3 locknuts
evenly to achieve correct, uniform gap.
7. As an additional test, apply 12 volts to the terminals of the PTO electric
clutch. The clutch should engage. If the clutch does not engage when
voltage is applied, replace the PTO electric clutch.
8. If the clutch removal is necessary; refer to
9. After you complete the PTO electric clutch testing, connect the clutch
electrical connector to the machine wire harness.
10. Lower the hood and secure it with the latches.
Figure 165
3. Access slot (3 each)
4. Locknut (3 each)
(Figure 165). The gap should be 0.4 mm (0.015 inch)
PTO Electric Clutch (page
Page 6–65 Electrical System: Testing the Electrical Components
5. PTO belt
(Figure 165).
6–78).