Motor Rebuild

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Contact us: bracket500@live..com Rebuild Motor Page

On this page we will explain how to take your motor apart and put it back together.
This is just for basic general purpose use, your motor will run a little better and you
won't set records, this is instructional only. This is done with common tools in your box.
Some of the work will have to be done at your local track or find someone to cut the
com and zap your magnets.

Motor we will use, Parma 16
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Rims and gears tool, gear puller and arm alignment tool.
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Part 1
First is remove the gear if you have one.
Now mark with a marker where the motor meets to endbell.
This will ensure you put it back the way it came apart.
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Mark the area where the motor screws are, so you won't
change the timing.
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Next you must get the brushes, held in place by springs.
See how they're mounted on the screws in case they fall off.
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Undo the spring one at the time and remove the brush.
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Now you have everything apart. Some of the people that
zap magnets don't need them removed, check fisrt with
whom you're going to have them zap.
In case you have to change the springs, take a look and
remember which way they're set up.
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Check: some motors have different size washers and
more than one, so keep count of the washers and which
side they came from.
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The Phenolic Spacers will go at the end of the stack
of washers on the arm.
This will be explained in the next rebuild.

You will need a new set of brushes for the rebuld.
Some racers also replace the springs.

Remember this is just a basic tear down and rebuild.

Part 2 the rebuild.

All your parts cleaned and ready for assembly
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It's a good idea to take an x-cto knife and clean the
burs
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Then take a ball point pen and run it in the groove.
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Now you can see a cut arm
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I noticed a lot of play back and worth when I set the
arm back in the can, to adjust that, add washers.
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After a few rounds of testing washers, it's ready.
Your local track should have a variety of washers for
this phase.
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I made sure to insert the hood alignment tool so my
brushes will sit properly. Slide it back and worth a
few times.
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Make sure to clean all your parts.
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Take a look on how your spings are set up and that
your alingment lines line up.
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Set the screws back in place that hold the end bell to
the can. Finnished Motor.
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Below see how to set up shunt wires.

A little more advanced by NZ Mark and Hannah.

The tools and bits we needed:

The last major thing was the motor.

We chose a PARMA Rotor motor because they are widely available and reasonable. Because its a Bracket car we only did a few things to get it race ready. We will not blueprint because there are plenty of people who can do that better.

We dis-assembled the motor and aligned the bearings/brush hoods. When all aligned we glued the endbell bush and soldered the can bush.

While the magnets were out we tapped the motor mount holes to 2-56.

We hand reamed the bushes to 2.0mm, put the magnets back in (correctly orientated using a small compass), spaced the arm so minimal movement and screwed on the endbell:

We radiussed the brushes

After fully assembling the motor we lightly lubricated the bushes hooked it up for 1/2 hour to a simple & cheap break in box we made:
When it was done flushed the motor with lighter fluid.

The break-in box was made from bits purchased from a local franchise, but Ive found everyone in USA can get the bits from Radio Shack:

4 "D" Battery Holder $1.89
Model: 270-396 | Catalog #: 270-396

Fully Insulated Alligator Clip Adapters $2.99
Model: 270-354 | Catalog #: 270-354

Just buy 3 D size batteries and you are in business.

We rechecked the alignment of the rear bushings and reamed to 3/32"; installed & wired the broken in motor; Installed the running gear and adjusted the gear/pinion we also tidied the wiring with heat shrink tube:

Shunts:

Shunt wires are used for a better connection
between your brushes and where you power hooks
up to the motor.
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Old springs on the left, a stronger spring on the right.
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New brushes and some silver shunt wire, you may use
copper wire, like your lead wire, stripped and turn it tight.
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You will need an insulator, that's the yellow wire cover
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On the spring, make sure to place some insulator cover.
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Crimp you shunt wire for a better connection also take a
file and widen the gap on the brush to set the shunt wire.
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Put your springs back on and make siuse that the
shunt wire is properly set in it's place.
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I would like to add, these are just examples on how you can rebuild your motor,
and like anything else there are many way to do so.

Gearing: Most racers have a way to gear their cars, I suggest to starts with a 10/56 set up.
More on this later.....

Any other suggestions are welcomed, just drop me an email.

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