Grizzly G0740 owner manual Service, Troubleshooting, Motor & Electrical

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 at (570) 546-9663. Note: Please gather the serial number and manufacture date of your machine before calling.

Troubleshooting

Motor & Electrical

Symptom	Possible Cause		Possible Solution
Machine does not	1.	motor will start, only backward.	1.	Correct out-of-phase wiring (refer to Page 17 for
start or a circuit				details).
breaker trips.	2.	stop button is engaged or at fault.	2.	rotate button clockwise until it pops out to reset it
				for operation; replace if not working properly.
	3.	spindle switch(es) are at fault.	3.	replace bad switch(es).
	4.	power supply is switched OFF at two-	4.	make sure two-speed motor switch and circuit
		speed motor switch or breaker.		breaker are turned ON.
	5.	Wall fuse/circuit breaker is blown/tripped;	5.	Verify circuit is rated for machine amp load;
		short in electrical system; start-up load too		troubleshoot and repair cause of overload; replace
		high for circuit.		weak breaker; find/repair electrical short.
	6.	Fuse has blown in machine electrical box.	6.	replace fuse; determine if overload is due to heavy
				operation; ensure power source has high enough
				voltage and power cord is correctly sized.
	7.	one or more safety switches or brake	7.	Verify chuck guard, spindle, and brake switches are
		switch are engaged.		not engaged.
	8.	thermal overload relay has tripped.	8.	turn the thermal relay cut-out dial to increase
				working amps and push the reset pin. Replace if
				tripped multiple times (weak relay).
	9.	motor connection wired incorrectly.	9.	Correct motor wiring connections (Page 90).
	10. safety/brake switch(es) at fault.		10. test all switches and replace as necessary.
	11. Contactor not getting energized/has burned		11. test for power on all legs and contactor operation.
		contacts.		Replace unit if faulty.
	12. Wiring is open/has high resistance.		12. Check for broken wires or disconnected/corroded
				connections, and repair/replace as necessary.
	13. motor is at fault.		13. test/repair/replace.
Loud, repetitious	1.	pulley set screws or keys are missing or	1.	inspect keys and set screws. Replace or tighten if
noise coming from		loose.		necessary.
lathe at or near the	2.	motor fan is hitting the cover.	2.	tighten fan, shim cover, or replace items.
motor.
Motor overheats.	1.	motor overloaded.	1.	allow motor to cool; reduce load on motor.
Motor is loud when	1.	excessive depth of cut or feed rate.	1.	Decrease depth of cut or feed rate.
cutting, or bogs	2.	spindle speed or feed rate wrong for	2.	refer to the feeds and speed charts in Machinery's
down under load.		cutting operation.		Handbook or a speeds and feeds calculator on the
				internet.
	3.	Cutting tool is dull.	3.	sharpen or replace the cutting tool.

Model G0740 (Mfg. Since 11/12) -73-