Next time, run it for a few minutes no-load before shutting it back
down. It will pull in cool air and not melt.
She's fried. Smell that burnt varnish? It's a big clue.
I agree. I burned up a Chiwanese hammer drill like that. I had kept it
running after drilling lots of holes in concrete and it was smoking,
but the running after the drilling cooled it down some. I didn't let
it run long enough to cool down after the last hole, and when I tried
to use it the next time, it was dead shorted.
Happiness lies in the joy of achievement and the thrill of creative effort.
-- Franklin D. Roosevelt
Took it apart - everything looks normal except the carbon brushes look
worn. Testing the ohm from the wires to the two brushes gives me OPEN
circuit in the coils. Does this prove that it is fried so I do not need
to put it back together? There are no visible fuses.
The field coils are open? Hmm, I suspect a thermal fuse. If there's
a silver pod somewhere in the windings, it has probably gone open.
You can probably get a replacement, or just short it out for a quick
test. Kind of rare for an overheated motor to fail open, generally
they would develop a short somewhere. Probably the heat built up after
shutdown and got hot enough to trip the thermal fuse. These are common
in these type of appliances. The fact they are one-time cutoffs
sounds like planned self-destruct as opposed to planned obsolescence.
When I worked in regional office, I got the reputation as Mr. Fixit.
Most of the female staff had "safety" oscillating fans at their work
stations, which, of course, never were turned off, thus injesting
airborn dust, lint, hair etc.
I would get a call, "Gerry, my fan quit" so I would tell them to bring
it to my desk and I would look at it.
When no one was looking, I would plug it in and turn it on.If it
would run slowly it would get bearing cleaning/lubrication. If it
showed no life, I would unplug it and insert a paper clip through the
cooling slots to short across the thermal fuse burried in the
windings, plug it in and the fan would run fine, at which point I
unplugged it, removed the paper clip and used red permanent marker to
label it "BURNED OUT SAFETY FUSE" and tell them to turn it in for a
I never botherd trying to explain that their fans would last longer if
they turned them off when they didn't need them.
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