beautypg.com

Troubleshooting – Grizzly H7760 User Manual

Page 25

background image

H7760 2" x 27" Belt Sander & 6" Grinder

-23-

Review the troubleshooting and procedures in this section to fix your machine if a problem develops. If you

need replacement parts or you are unsure of your repair skills, then feel free to call our Technical Support

department at (570) 546-9663.

SECTION 7: SERVICE

Troubleshooting

SYMPTOM

POSSIBLE CAUSE

CORRECTIVE ACTION

Motor will not start.

1. Low voltage.
2. Open circuit in motor or loose connections.

1. Check power line voltage and correct if necessary.
2. Inspect all lead connections on motor for loose or

open connections.

Motor will not start;
fuses or circuit break-
ers blow.

1. Short circuit in line cord or plug.

2. Short circuit in motor or loose connections.
3. Incorrect fuses or circuit breakers in power

line.

1. Inspect cord and plug for damaged insulation or

shorted wires.

2. Inspect all motor connections for loose or shorted

terminals or worn insulation.

3. Install correct fuses or circuit breakers.

Motor overheats.

1. Motor overloaded.

1. Reduce load on motor.

Motor stalls (result-
ing in blown fuses or
tripped circuit).

1. Motor overloaded.
2. Short circuit in motor or loose connections.
3. Low voltage.
4. Incorrect fuses or circuit breakers in power

line.

1. Reduce load on motor.
2. Inspect connections on motor for loose or shorted

terminals or worn insulation.

3. Check power line voltage and correct if necessary.
4. Install correct fuses or circuit breakers.

Machine slows when
operating.

1. Workpiece pressure is too great.

1. Reduce workpiece pressure on wheel.

Wavy condition on
surface of work-
piece.

1. Machine vibrating.
2. Workpiece not being held firmly.
3. Wheel face uneven.
4. Wheel is too hard.

1. Ensure machine is securely mounted.
2. Use a holding device to firmly retain the workpiece.
3. Dress the grinding wheel.
4. Use softer wheel, or reduce the feed rate.

Lines on surface of
workpiece.

1. Impurity on wheel surface.
2. Workpiece not being held tightly.

1. Dress the grinding wheel.
2. Use a holding device to firmly retain the workpiece.

Burning spots or
cracks in the work-
piece.

1. Workpiece pressure is too great.
2. Coolant required.

3. Improper type of grinding wheel.

1. Reduce workpiece pressure on wheel.
2. Add an optional coolant system or cool the work-

piece more frequently.

3. Try a wheel which is softer style or a coarser grit.

Wheel dulls quickly,
grit falls off.

1. Workpiece pressure is too great.
2. Wheel is too soft.
3. Wheel diameter too small.
4. Bad wheel dress.
5. Defective wheel bonding.

1. Reduce workpiece pressure on wheel.
2. Select a wheel with a harder bond.
3. Replace the wheel.
4. Dress the wheel.
5. Consult manufacturer of grinding wheel.

Wheel clogs and
workpiece

shows

burn marks.

1. Wheel is too hard.
2. Feed rate too slow.

3. Bad wheel dress.
4. Coolant required.

1. Select a wheel with a softer bond.
2. Increase the rate of movement of the workpiece onto

wheel.

3. Dress the wheel.
4. Add an optional coolant system or cool the work-

piece more frequently.