UnlockingBoredom wrote:I have tested the motor and it works good (I still need to attach more wire and wire it to a switch and then to a cigarette lighter plug) to finish it.
If possible, you might want to loosen the thru-bolts on that motor and just barely crack open the back plate of the motor and examine the brushes and commutator within, don't open too far as you will drop the brushes, if the brushes are low, that is to say there is only a 1/4 inch between the brush cable and the area riding the commutator, you will want to consider sourcing new brushes before they begin arcing and hose up your commutator ruining the motor.
Replacement is rather easy, pull the motor, remove the thru-bolts and back plate dropping the brushes, then remove the pulley and deburr the shaft with some 320 grit wet-or-dry sandpaper (if required), once cleaned up lube the shaft with some moly based grease and pull the armature out of the front plate.
Once pulled examine the bearing surfaces of the shafts, if discolored or slightly marred give them a few swipes with a strip of 1500 grit W/D sandpaper, you're are not trying to remove any metal, just produce a nice shiny surface, remove all grit with a clean lint free wipe and chuck the large part (windings) of your armature up on a bench vice (commutator facing up) protected from damage by the jaws with a couple blocks of wood.
Closely examine the commutator, if the brushes haven't undercut it too much, say 1/32 of an inch or less you should be good to go, take a strip of emery cloth 120 grit or lighter and just slightly burnish the undercut, you can hold the strip with both hands and stroke it back and forth across the back of the commutator a couple of times then loosen the vice, rotate the armature a quarter turn and repeat until you have gone 360 degrees.
Again remember you are not trying remove too much copper, you're just trying to provide your new brushes a flat clean surface to ride upon.
Next step is to very carefully examine the commutator for any copper bridges from one segment to another, it is common for worn brushes, under load to arc and actually drag copper from one segment to another, these bridges short out the windings of the armature, causing the motor to produce vibrations and draw more amperage than it should, eventually these bridges will cause the bridged windings of the armature to burn up, rendering the motor useless.
Simple solution is to use something like a dental pick and just scratch away the copper bridges, no shorts no problems.
Then turn you attention to the bushings in the front and back plate (I am guessing it is not bearing based), you will probably find a bronze bushing surrounded by a felt ring and chances a lot of caked up grease, your mission is to remove, as much as possible the caked up grease while being very careful not to eff with felt ring, which by now is probably ready to fall apart.
Once you have that done, then very carefully and with a minimum amount of mineral sprits and a Q-Tip clean out the center of the bushings, if they are scored or burnt, oops too bad, you cannot practically fix that, so just plug forward.
Coat the inside of the bushings with a slather of moly grease and then soak into the felts as much as they will absorb with 20 weight oil.
Now for assembly.
Unsolder and remove the old brushes and Install your new brushes into the brush holders of the rear plate, press the brushes back into the holders and slide the armature into the back plate including the rear bushing and brush assembly.
Now comes the fun part, that motor looks to me like a permanent magnet motor.
So lock the back plate in a vice by it's nipple, with the armature inserted into the back plate bushing and the brushes, then while holding the armature at the bottom bring the housing and let it latch magnetically to the armature, from there you can push it down into place and rotate it to where the thru-bolts line up, then repeat the lube job for the front plate and set it into place.
Re-vice it between the wood blocks and hit it with 12 volts and see how it spins up, if you did well you have a motor that will probably outlast any need you have for it.
Oh BTW drop the cigarette lighter cord, too much of a voltage drop and piss poor connections, either hardwire it or use an Anderson connectior.
Wayne