SECTION 5: SERVICE

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 at (570) 546-9663.

Troubleshooting

Motor & Electrical

Symptom

 

 

Possible Cause

Possible Solution

Motor will not start.

1.

Low voltage.

1.

Check power line for proper voltage.

 

 

 

 

 

2.

Open circuit in motor or loose connections.

2.

Inspect all lead connections on motor for loose or open

 

 

 

 

 

 

 

 

connections.

 

 

 

 

 

Motor will not start;

1.

Short circuit in line cord or plug.

1.

Inspect cord or plug for damaged insulation and shorted

fuses

or

circuit

 

 

 

wires.

breakers blow.

 

2.

Short circuit in motor or loose connections.

2.

Inspect all connections on motor for loose or shorted

 

 

 

 

 

 

 

 

terminals or worn insulation.

 

 

 

 

 

3.

Incorrect fuses or circuit breakers in power line.

3.

Install correct fuses or circuit breakers.

 

 

 

 

 

Motor overheats.

1.

Motor overloaded.

1.

Reduce load on motor.

 

 

 

 

 

Motor stalls (result-

1.

Short circuit in motor or loose connections.

1.

Inspect connections on motor for loose or shorted termi-

ing in blown

fuses

 

 

 

nals or worn insulation.

or tripped circuit).

2.

Low voltage.

2

Correct the low voltage conditions.

 

 

 

 

 

3.

Incorrect fuses or circuit breakers in power line.

3.

Install correct fuses or circuit breakers.

 

 

 

 

 

4.

Motor overloaded.

4.

Reduce load on motor.

 

 

 

 

 

 

Machine

slows

1.

Operator is using too much pressure.

1.

Use less pressure when grinding.

when operating.

 

 

 

 

 

 

 

 

 

 

 

 

Wavy

 

condi-

1.

Machine vibrating.

1.

Make sure machine is securely mounted on a solid sur-

tion on

surface

of

 

 

 

face.

workpiece.

 

 

 

2.

Workpiece not being held firmly.

2.

Use a holding device to firmly retain the workpiece.

 

 

 

 

 

3.

Wheel face uneven.

3.

Dress the grinding wheel.

 

 

 

 

 

4.

Wheel is too hard.

4.

Use softer wheel, or reduce the feed rate.

 

 

 

 

 

Lines on surface of

1.

Impurity on wheel surface.

1.

Dress the grinding wheel.

workpiece.

 

 

 

2.

Workpiece not being held tightly.

2.

Use a holding device to firmly retain the workpiece.

 

 

 

 

 

 

 

 

Burning

 

 

spots

1.

Improper type of grinding wheel.

1.

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

or cracks

in

the

2.

Improper feed rate.

2.

Slow down the rate of movement of the workpiece into

workpiece.

 

 

 

 

 

 

wheel.

 

 

 

 

 

3.

Coolant required.

3.

Add optional coolant system or introduce coolant by

 

 

 

 

 

 

 

 

hand.

 

 

 

 

 

Wheel dulls quickly,

1.

Depth of cut too great.

1.

Slow down the rate of movement of the workpiece into

grit falls off.

 

 

 

 

 

 

wheel.

 

 

 

 

 

2.

Wheel is too soft.

2.

Wheel too soft for the material being ground, select

 

 

 

 

 

 

 

 

harder bond.

 

 

 

 

 

3.

Wheel diameter too small.

3.

Replace the wheel.

 

 

 

 

 

4.

Bad wheel dress.

4.

Dress the wheel.

 

 

 

 

 

5.

Defective wheel bonding.

5.

Consult manufacturer of grinding wheel.

 

 

 

 

 

 

 

Wheel

clogs

and

1.

Wheel is too hard.

1.

Wheel too hard for the material being ground, select

workpiece

shows

 

 

 

softer bond.

burn marks.

 

 

 

2.

Feed rate too slow.

2.

Increase the rate of movement of the workpiece into

 

 

 

 

 

 

 

 

wheel.

 

 

 

 

 

3.

Bad wheel dress.

3.

Dress the wheel.

 

 

 

 

 

4.

Coolant required.

4.

Add optional coolant system or introduce coolant by

 

 

 

 

 

 

 

 

hand.

 

 

 

 

H7758/H7759 8" & 10" Bench Grinders

 

-17-

Page 19
Image 19
Grizzly H7758, H7759 owner manual Service, Troubleshooting