(Fwd) RE: surging, motor

["David Roden" <roden ald net>]

Christopher Meier <Christopher Meier cwix com> wrote:

> Just to be clear;  
> occasionally, when at a complete start,
> when I advance the speed selector, the
> contactors clack on, but the motor doesn't
> budge or make a peep - nada nothing. 

Does the ammeter deflect upscale when you do this?  If not, you may have 
one or more open windings in the armature.  The wire might be just 
detatched from the commutator segment.  These are usually silver-soldered 
to withstand heat, so you can't just solder it back on with a 25-watt 
iron (alas).

It might also be just a cruddy com segment.  In any case you should not 
continue to run it.  If you have a motor shop you trust, have them do a 
test.  If you need to find a shop, call a couple local golf courses and 
ask the mechanic for the name of the shop that does motor work for him.

If the ammeter does deflect (especially if it deflects *a lot*), it might 
suggest some pretty serious friction in bearings or brushes/com.  
Friction would have to be *very* high; starting torque on these motors is 
pretty good.  This seems unlikely, since you're able to rotate the motor 
manually.

>  I turn the speed selector off, reach down, rotate the motor pully 
> slightly, then advance the speed selector, and it works fine again.
> Like a dead spot or something.

A field problem doesn't seem so likely since you say it starts on its own 
when you nudge the pulley.  I agree with the other posts; check the 
commutator, brushes, and armature windings.

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