Section 7: Service; Troubleshooting - Grizzly G0776 Owner's Manual

SECTION 7: SERVICE

Review the troubleshooting and procedures in this section if a problem develops with your machine. If
you need replacement parts or additional help with a procedure, call our Technical Support. Note: Please
gather the serial number and manufacture date of your machine before calling.
Symptom Possible Cause
Machine does not 1. Emergency stop button depressed/at fault.
start or a circuit 2. Main power switch OFF or at fault.
breaker trips. 3. OFF button not reset.
4. Plug/receptacle at fault/wired wrong.
5. Incorrect power supply voltage or circuit
size.
6. Power supply circuit breaker tripped or fuse
blown.
7. Motor wires connected incorrectly.
8. Wiring open/has high resistance.
9. Start capacitor at fault.
10. Motor at fault.
11. Spindle rotation switch at fault.
Motor stalls or is 1. Machine undersized for task.
underpowered.
2. Feed rate/cutting speed too fast.
3. Wrong workpiece material.
4. Belt(s) slipping.
5. Motor wired incorrectly.
6. Plug/receptacle at fault.
7. Gearbox at fault.
8. Motor overheated.
9. Run capacitor at fault.
10. Pulley/sprocket slipping on shaft.
Machine has 1. Motor or component loose.
vibration or noisy
operation.
2. Bit chattering.
3. V-belt(s) worn or loose.
4. Motor fan rubbing on fan cover.
5. Motor mount loose/broken.
6. Pulley loose.
7 Machine incorrectly mounted.
8. Motor bearings at fault.
9. Workpiece or chuck at fault.
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Troubleshooting

Possible Solution
1. Rotate button head to reset. Replace.
2. Turn main power switch ON or replace if at fault.
3. Press OFF button completely until it clicks.
4. Test for good contacts; correct the wiring.
5. Ensure correct power supply voltage and circuit
size.
6. Ensure circuit is sized correctly and free of shorts.
Reset circuit breaker or replace fuse.
7. Correct motor wiring connections.
8. Check/fix broken, disconnected, or corroded wires.
9. Test/replace.
10. Test/repair/replace.
11. Test/replace switch.
1. Use sharp tools at correct angle; reduce feed rate/
depth of cut; use coolant if possible.
2. Decrease feed rate/cutting speed.
3. Use correct type/size of metal.
4. Tension/replace belt(s) (see Page 83); ensure
pulleys are aligned.
5. Wire motor correctly.
6. Test for good contacts/correct wiring.
7. Select appropriate gear ratio; replace broken or
slipping gears.
8. Clean motor, let cool, and reduce workload.
9. Test/repair/replace.
10. Replace loose pulley/shaft.
1. Inspect/replace damaged bolts/nuts, and retighten
with thread locking fluid.
2. Replace/sharpen bit; index bit to workpiece; use
correct feed rate and cutting RPM; retract tool
holder and position workpiece closer.
3. Inspect/replace belts with a new matched set (see
Page 83).
4. Fix/replace fan cover; replace loose/damaged fan.
5. Tighten/replace.
6. Re-align/replace shaft, pulley set screw, and key.
7. Tighten mounting bolts; relocate/shim machine.
8. Test by rotating shaft; rotational grinding/loose shaft
requires bearing replacement.
9. Center workpiece; replace defective chuck.
Model G0776 (Mfd. Since 7/14)