[Newbie] G0704 Over Heating, No Start

Deucetrooper

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As the title states. My mill overheated and blew its fuse and will not restart. Fuse will blow upon restart attempt.

Can anyone recommend a repair station in the vicinity of Victorville, California.

Thanks
 
Good odds you need a new motor. Mine burned out, and it seems to be a common fault on these units. The replacement motor I got from Grizzly seems to be a better unit than the original part. I don't know of a place that repairs them.
 
First how old is your 704? It could be the motor or the controller board.
 
Thanks for the replies thus far.

Made in 2011. I forgot to mention the spindle moves forward or rearward when spun by hand.
 
i had to put a new board in my G0720 vintage 2012.
it only cost me $480 OUCH !!
 
First thing I'd do is disconnect the motor leads from the board (make sure you make a note or take photo to show where they go!) and then see if the fuse still blows - it will help determine if the board is bad or the motor is bad. Unfortunately, it won't tell you much if both are bad, but it will give you a starting point. Not quite sure what you mean when you say that the spindle moves forward or rearward when spun by hand - does it turn freely? You can disconnect the gears by setting the speed selector between the two speeds - when you do that do you feel less resistance when you turn the spindle by hand? If so, put it in high gear and short the motor leads together (unplug the power cord for this) while turning the spindle by hand - you should feel more resistance to turning the spindle when the leads are shorted together than when they are are not shorted together.
 
First thing I'd do is disconnect the motor leads from the board (make sure you make a note or take photo to show where they go!) and then see if the fuse still blows - it will help determine if the board is bad or the motor is bad. Unfortunately, it won't tell you much if both are bad, but it will give you a starting point. Not quite sure what you mean when you say that the spindle moves forward or rearward when spun by hand - does it turn freely? You can disconnect the gears by setting the speed selector between the two speeds - when you do that do you feel less resistance when you turn the spindle by hand? If so, put it in high gear and short the motor leads together (unplug the power cord for this) while turning the spindle by hand - you should feel more resistance to turning the spindle when the leads are shorted together than when they are are not shorted together.

OK, thanks for the guidance.

I (took photo) then disconnected the motor leads. Fuse did not blow. Digital readout read 7100 for a second then was steady at 0. Spindle does move freely by hand.
I shorted the motor leads and felt a minute bit of resistance.
Out of curiosity, I pressed the motor leads to a 9V battery. It spun the spindle slowly.
I reconnected the motor leads and plugged the power cord. The RPM reading showed a HIGH reading of 1200 on L, so I turned off the mill and started it on H. it read 2100. I turned the mill of and checked for smoke, none. I turned on the mill again, however the digital display would jump to 7100 then 0 reading. Motor would no longer turn on. There was a smell of melted plastic or rubber present. I have since disconnected the power plug.

?
 
I'm still mulling this over - by the way, good thinking on the 9 volt battery! If you have a higher voltage DC source available, like an 18 volt cordless drill battery, you might see if the motor still runs with DC applied. The RPM indicator is a separate board from the controller, but it does get it's power from the controller, if I remember correctly. If the motor still runs on a battery, I'm inclined to think the problem may be the control board.
 
Dan,

I just applied the motor leads to an 18 volt cordless drill. Motor runs! Thanks for your continued assistance.

George
 
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