Locked up motor after long downhill run?

[scottyb]

I have had good results with a 2-3 amp 12v charge on an 8v for 30-45 minutes... Physically check the voltage & case temp every half hour. (11v max) These batteries hate to be left in a low state of charge.

[dbarrym]

Originally Posted by Stevegrmich

The two phillips head screws that hold the motor access cover in place should be threaded into a molley-type 1/4"-20 blind nut fastener that is secured into the body panel . . .

Mine has a metal plate molded into the body but no captive nuts, it used two separate 1/4-20 nuts. I'll install some captive nut inserts when I'm done.

[dbarrym]

OK so I had a spare hour and pulled the motor without any drama. It's getting dark so I took a few quick cellphone pics. I pulled the two small bolts and removed the armature, but the outer case does not want to come off. Nothing loose inside and no debris or obvious signs of serious damage to my inexperienced eyes.

Any comments on the condition of the brushes, armature, commutator, etc are welcome. I don't see any major damage that would lock up the motor solid, but I do see some scratches/grooves and rust on the surface or the armature that I would not expect to see. The magnet/coil surfaces are very black with brush dust, with some browning to black discoloration on the windings behind the magnet surfaces. The rear bearing is free and tight as well.

The brushes seem intact, the wiper/commutator surfaces don't seem burned or too heat damaged....I guess I don't see where the motor could have been the cause? On the other hand, it did not spin as free as I'd expect when I was pulling it off, some grittiness in spots (maybe from the rust?).

Comments welcome from the experts...use this motor or is there something you can see that says it is bad? I expected to see a burned and melty interior, given how solid it was locked up when it failed...?

[Stevegrmich]

Originally Posted by dbarrym

Mine has a metal plate molded into the body but no captive nuts, it used two separate 1/4-20 nuts. I'll install some captive nut inserts when I'm done.

I based my answer on the individual parts list for my cart . . I will have to take a look at what I really have . . the nuts on mine are part of the body and may have an aluminum brace behind the body with the nuts attached . . parts list diagram does show the blind nuts being assembled to body from outside of body panel . . . now I am curious too . . .

[shadowman]

nothing with those pics jumps out at me.......have you spun the rear wheels with motor out to see what it sounds and feels like?..............................

[Stevegrmich]

I'd have the armature turned down a little to clean it up . . .

[shadowman]

see i take stuff like that for granted..........( cleaning ) i figure when someone looks at their part and sees that its automatic as far as cleaning goes................

[dbarrym]

Originally Posted by shadowman

nothing with those pics jumps out at me.......have you spun the rear wheels with motor out to see what it sounds and feels like?..............................

Yes, it spins free with no undue drag, noise, or problems.

Given the scratches and marks on the armature, I'm wondering if there was a chunk of rust or something that could have jammed it from rotating, though nothing fell out (other than brush dust). I'd prefer not to go through the hassle of sending out the motor for a rebuild but can't think of anything else that could cause a problem...Brakes are free and not binding as well.

Confused.....

[ForBruce]

is the bearing on the end of the shaft noisey when you spin it.... They only cost about $10 from a Bearing supplier . As long as you have the motor apart WHY NOT ....invest

[dbarrym]

Originally Posted by ForBruce

is the bearing on the end of the shaft noisey when you spin it.... They only cost about $10 from a Bearing supplier . As long as you have the motor apart WHY NOT ....invest

Second thing I checked - the bearing feels good, no rumbling or rough spots.

Since the armature is way too big for my small shop lathe, I think I'll just order a PQ Bandit motor and go from there. The charger arrived today and I'm recharging the batteries now, will check them later (gotta pick up a hydrometer).

Thanks for the input, not sure what else I can check at this point until I get a new motor installed?