Sh*tpart winch!

Hi all,

I brought a job lot of spares and included was a db12000 winch (solenoid doesn't work)
I have stripped it all down and given it a good clean and replaced the brush holder.

It won't spin up when I earth the winch, put power to F1 and short F2 with A terminals and appears to short much more than it should. Both the electromagnets and x2 brushes are insulated from the motor casing.

The only thing I thought it could be is the commutator - I noticed that every commutator bar is connected i.e. I connect earth tester to one ring and every other ring is also earthed?

If anyone is good with winch motor electrics and has a suggestion please help!

Thanks,
Matt

I tend to find that if every segment on a commutator is connected to every other, then the armature windings have failed. The very thin coat of insulation, almost like a lacquer, on the copper wires gives up the ghost as a result of old age, moisture, overheating and suchlike, so they short out rather than have the current pass right round the windings.
Commutators short out too sometimes of course as a result of the build up of dirt and metal dust between the segments, but if you've cleaned this out and it is still shorting it is probably the windings themselves.

Depending upon the build of the motor it is not unusual for each segment of a commutator to show a low resistance reading to the other segments. What you don't want is a low resistance reading between any segment of the commutator and the main shaft of the motor as that shows an insulation breakdown.

Have you got a barn or large garage. It'll make a great door stop.