Gravely 990014, Руководство по обслуживанию

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through the coil, magnetizing the coil pulling the
armature onto the rotor with sufficient force to hold the
two pieces together, effectively connecting the output
and the input shafts together. Pulling the armature
against the rotor pulls it away from the brake, releasing
the brake.
Engine Electrical Components
Engine servicing and repair should be referred to local
engine manufactures service centers that have the
service information and parts available to properly
service the engine. Gravely dealers should be able to
test engines and engine components to pinpoint
troubles and narrow them down to properly advise the
engine serviceman.
12.10 CHECKING THE PTO CLUTCH
Measure Clutch Coil Resistance
1. Turn engine and PTO switch off.
2. Disconnect clutch wire connections.
3. Select meter to check ohms.
4. Connect meter leads wires in clutch connector.
5. If meter reads below 2.50 ohms or above 3.50
ohms, then the clutch has failed and needs to be
replaced.
6. If meter reads between 2.50 to 3.50 ohms, proceed
to Measure Clutch Current Draw.
Measure Clutch Current Draw
1. Turn engine off.
2. Disconnect clutch wire connection.
3. Select meter to check amps (10 amp scale).
4. Connect one meter lead wire to one wire in clutch
connector at A (See Figure 45).
5. Connect the other meter lead wire to the
corresponding wire in the mating connector at C.
6. Connect a short wire from D to B in both
connectors.
7. Turn PTO switch on.
8. If meter reads below 3.5 amps, the problem would
be in the electrical system leading to the clutch
(battery, relay switch, etc.).
12.11 PROMASTER 300 ELECTRICAL
Ignition Switch
Check procedure:
1. Unplug the ignition switch and remove it from the
instrument panel.
2. Set a VOM in the ohm (Rx1) position. Connect one
lead to the "B" pin.
3. Turn the ignition key to position 1. Sequentially
touch pins R, I, A, S and the case with the free
meter lead. No circuit (infinity) should be indicated.
4. Turn the key to position 2 and hold. Sequentially
touch pins R, I, and A with the free lead. A circuit
(zero ohms) should be indicated. Touch the free
lead to the case. No circuit (infinity) should be
indicated.
Figure 45
Figure 46
Key
Position Function Circuit
1 Off None
2 Start B+R+I+S
3 Run B+R+I+A