Motor for electric leaf blower

sandpaper.

Respectfully suggest you buy a broom :-)

It depends on how good it was to start with. If it were built in 1960 by a reputable manufacturer you could have the motor rebuilt by turning down the commutator (that's probably what you sanded) and replacing the brushes.

If there's enough metal left on the commutator to turn it down, and the brushes can be replaced, then yes, you can probably bring the thing back to life.

If you think the commutator is clean and smooth enough, then make sure that you've cleaned any conductive dust from between the commutator segments, replace the brushes (or at least clean them up, too), and give it a whirl.

Thanks.

The brushes weren't worn that much but I will clean them up.

I have replaced brushes on alternators, but this motor has a much faster r.p.m. so it stands to reason that it is gonna wear down much faster.

Andy

sandpaper.

Respectfully ignored as poor advice.

Are there burned, microscopically melted spots at the edge of one of the commutator bars? That is a strong sign of a shorted armature winding.

Jon

Thanks for your help.

Not that I can see with the unaided eye.

I checked the brushes, and the end is very slightly grooved like it wasn't making a good contact.

Others I have seen are shiny on the end.

Should I polish the end and retry it ?

The motor is only a couple years old.

I will take a picture and get back.

Andy

sandpaper.

clean between the commutator sectors replace the brushes.

sandpaper.

There are 2 pictures here.

Try an ohmmeter on the brushes and rotate the shaft. It should alternate

between two values depending on the position if the brushes are aligned on one pair of windings or two. Even better would be to apply a safe, low AC voltage (6-12 VAC) and check the current draw. A shorted winding will draw a lot more current. You may even be able to feel some torque on the shaft or it may try to run slowly, and you may see where it hesitates.

Or you can grab an obstructionist Republican politician by the feet and he will blow away the leaves with hot air :)

Paul

You may have found something.

Ohmmeter is showing 0 ohms no matter what position the commutator is at.

What does than mean ?

Andy

..

on

AC

raw a

or

he

Brushes worn down so much they do not make contact?

Dan

Motor1_zps0b0fc7...

Zero ohms indicates a short circuit, not open.

In this case, zero ohms most likely indicates that the resistance of the armature is lower than what the meter is capable of registering. The

dose not mean much actually.

If that is a low voltage motor, something less than 50volts, your meter most likely won't read anything useable because the normal readings for that motor will most likely be less than an ohm and lots of meters just won't display any usable data down there. That is, DMM's that cost less than 100 bucks.

What you should be doing is measure for leakage to ground/core. Any reading less than 500k ohms is suspect. If you have a mega meter that could be useful, too.

Also, if it has a PM (permanent magnets)? They maybe weak from heat and that is going to cause lots of amps and no torque, but it'll spin like hell if you can get it running. Once the magnets start degrading for what ever reason, the heat from efficiency loss just exponentially degrades the motor.

I am guessing you may have a series motor. Those motors are only limited in RPM's with respect to the load on them. I've seen those short a few turns of wire with out showing any ground shorts. You should take note the color of the magnetic wire if you can see it. It should not look like it has been subjected to heat! When this happens to these types of motors, you'll see more brush arcing than normal, even with a clean commutator and new brushes.

Have a good day..

Jamie

ttdesign.com

You are absolutely right. Zero ohms does indicate a short. But in the original post Andy said the motor did not run and the switch was good. So I assumed when he said Zero Ohms, he really meant the meter did not indicate anything and he really had a open. Not likely to be a dead short and not have a lot of excitement with 120 volts applied. Of course he may have a battery operated leaf blower................ Or he has it plugged into a dead outlet.

Dan

He said in a later followup:

That's why I suspected a bad winding or connection to a commutator section.

The proper way to test this motor is with a "growler":

Here's a video of one being used on a 110V reel motor armaturer:

Paul

Paul

Some other educational videos, one on testing:

and one on repair:

Paul

It been interesting gentlemen.

Looks like Toro doesn't want their products repairable by the consumer.

Minimum order for a replacement motor is 500.(Mamco motor)

I think the armature is shorted out.

Andy

Check your Salvation Army store and the Goodwill. I bought a Sears leaf blower motor for $ 4. Did not include all the parts as nozzles and tubing.

Dan

sandpaper.

I fixed it.

Those ridges in the brushes weren't normal.

After sanding them smooth, the leaf blower is against producing 180 m.p.h. winds.

I think the brushes are made of graphite.

Andy