Sander works it just dont have hardly any power just wondering if that was the brushes causing that problem

No, that's probably where the motor brushes are at. Should have two of them.

Brushes wear out often. Unscrew the brush caps and see if they are worn really low or if the springs are broken. If there is any burning on them, then replace them. Also those brushes sometimes stick in the brush holders because of the amount of dust. When you remove the brush caps, blow out all the dust you can.

The wires that go to the brush holders have springs that wrap around the inside of the brush holder (see picture). Check and see if those springs are broken or if those wires are not connected. Sometimes the fields go out in those but it's not too common. Almost never is it the armature (unless a bearing causes it but that's a mechanical failure, not an electrical issue).

Chcke th brushes for a sticking condition. You may just need to take the brushes out and clean the holders.

Likely the gear belt that drives the drive rollaer has failed. Either it is totally gone or the teeth in a spot have been destroyed and the motor is just spinning the sprocket in the belt. The belt is about 1/2 inch wide and is covered by a belt guard.

Similar problem with my 7500 2x18" belt sander. Replaced the brushes today (didn;t look bad{ had sander 3 months to sand pistol grips. Sparks were flying from motor so replaced the brushes. Skil runs very slugis like its booging down, I think the only other possible solution is new bearings for me and perhaps you..

The best way to sand drywall is to use a pole sander (manually). You can pick them up for about $20.

This particular machine tends to leave grooves in the drywall compound if you are not familiar with how to use it.

If you should have any questions about "Drywall Finishing/Patching", or know someone who does, put your questions to Category:"Tools- Building & Power- HAND TOOLS" at FixYa.com

Thanks,

Jim

You're plugged in to a dead outlet, OR the rotor brushes are not in contact with the rotor, OR the power cord is partially severed,

Motor may just need new brushes, Cooling vents may be clogged with dust. or bearings in the motor or front roller maybe bad. Causing excessive drag
blow it all out with compressed air or shopvac
look for external brush caps (2) oppsite from each other take them out to be sure they slide freely, sometimes one gets hug up and doesn't make good contact

It's usually not the brushes but the commutator that needs cleaned. The commutator is the surface the brushes ride on. Go to Walgreens and buy a multi-surface nail file, one of the soft ones that are about 3/4" square with different colors for different grits. Don't start at the coarse grit!! Start at the medium grit and lightly drag it over each section in a smooth arcing motion, when the commutator surface is shiny it's clean, then replace the brushes with new ones.

there isn't an internal fuse. by the sounds of it you probably have a short, a bad brush, or some arcing.

if you use your sander for fine sanding (100+ grit paper) you have to make sure to clean out the motor housing. Fine sanding dust, like any fine dust, creates alot of heat when aerated and can melt the plastic brush holders or can cause the electricity to arc from one wire to another inside the housing.

my advice is to take the 8 (i think it's 8) screws out of the side of the gun and carefully pull the halves apart. there isnt alot you can mess up inside and just visually inspect the wires for burns or melting on the brush holder.

here's a breakdown if you need it.
http://www.makita.com/en-us/Assets/images/Products/_PartsBreakdowns/PB_GV5000.pdf

if you find something inside that you're not sure of, or if you have any additional info i'll keep checking in on this.