Grizzly G0750GV Owner's Manual page 69

Motor & Electrical (Cont.)
Symptom Possible Cause
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.
Lathe Operation
Symptom Possible Cause
Entire machine 1. Workpiece is unbalanced.
vibrates upon
startup and while 2. Loose or damaged V-belt(s).
running.
3. V-belt pulleys are not properly aligned.
4. Worn or broken gear present.
5. Chuck or faceplate is unbalanced.
6. Gears not aligned in headstock or no
backlash.
7. Broken gear or bad bearing.
8. Workpiece is hitting stationary object.
9. Spindle bearings at fault.
Bad surface finish. 1. Wrong spindle speed or feed rate.
2. Dull tooling or poor tool selection.
3. Tool height not at spindle centerline.
4. Too much play in gibs.
Tapered tool difficult 1. Quill is not retracted all the way back into
to remove from the tailstock.
tailstock quill. 2. Contaminants not removed from taper
before inserting into quill.
Cross slide, 1. Gibs are out of adjustment.
compound rest, or 2. Handwheel is loose or backlash is high.
carriage feed has
sloppy operation. 3. Leadscrew mechanism worn or out of
adjustment.
Model G0750GV (Mfd. Since 03/18)
Possible Solution
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
(Page 73).
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.
Possible Solution
1. Re-install workpiece as centered with the spindle
bore as possible.
2. Re-tension/replace the V-belt(s) as necessary
(Page 73).
3. Align V-belt pulleys.
4. Inspect gears, and replace if necessary (Page 49).
5. Re-balance chuck or faceplate; contact a local
machine shop for help.
6. Adjust change gears and establish backlash
(Page 47).
7. Replace broken gear or bearing.
8. Stop lathe immediately and correct interference
problem.
9. Reset spindle bearing preload or replace worn
spindle bearings (Page 77).
1. Adjust for appropriate spindle speed and feed rate
(Page 46).
2. Sharpen tooling or select a better tool for the
intended operation.
3. Adjust tool height to spindle centerline (Page 44).
4. Tighten gibs (Page 70).
1. Turn the quill handwheel until it forces the tapered
tool out of quill.
2. Clean the taper and bore, then re-install tool.
1. Adjust gibs (Page 70).
2. Tighten handwheel fasteners, adjust handwheel
backlash to a minimum (Page 69).
3. Adjust leadscrew to remove end play (Page 70).
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