Atomic motor hot brush

Try cleaning the brush tube, brush and spring.

Another poster recommended using a small brass brush that is used to clean gun bores.

I purchased a 22 caliber one.

First I clean the tube with mineral spirits on a Qtip.
Then the gun cleaning brush,

Finally a second cleaning with a fresh Qtip moistened with mineral spirits.

Your spring could have the wrong tension. How does it compare to the spring that does not get hot?

Your brush could be dirty, or might have gotten some oil on it.

If there is oil on it, in my experience, it needs to be replaced.

The oil soaks into the brush. Clean it, and the surface oil is cleaned away.

But after a while, the oil seeps out and fouls the brush again.

I would only replace brushes in pairs.

Same goes for the springs.

If they are OK, I usually reuse the springs because IMHO the coil springs that are available today do not provide the correct tension.

How do you know it is overheated?  What is the problem or what does it look like?

The brush holders get hot to the touch.

I will try the cleaning steps advised. Brushes and springs are new, but I think the spring tension issue may be the culprit. It ran ok for a while, then stopped,and smoked. The spring had contracted to 1/2 size.

I'd use something like DeoxIT-D5 on the brush holders, sounds like you have poor contact there.

I found some "new old stock" brush springs, and that seems to have done the trick. Thanks to all.

quote:

I'd use something like DeoxIT-D5 on the brush holders, sounds like you have poor contact there.

I use a number of products from Caig Labs, including Deoxit.

If available, I'd suggest using the Deoxit as the last step, after getting the majority of the gunk out with mineral spirits and drying the part.

Caig labs fader cleaner/lube has fixed problems with noisy pots for me a number of times.

The only down side on Caig products are their cost. But only a little is used, so a bottle lasts a long time.

I have begun using only the new-style brushes with the embedded copper lead when I service an engine.  The current is conducted directly through the wire, not the spring and brush tube, eliminating most of the heating.  This also reduces arcing.

How do you attach the shunt to anything on an Atomic motor with the closed end brush tube and the coil spring?  Brushes with shunts would be great on the 622 type brush plate with the torsion springs and the open end brush holders.

I haven't actually tried this, but:

The coil spring only needs a rim to contact.  I think you could ream out the hole in the end of the brush holder enough to pass the shunt, but still leave enough lip for the spring.  It would be important to remove any burrs so that the shunt braid can move freely.

One of my PW F3s that I built from parts has the old-style brush plate.  I will try this next time I am inside that engine.  The F3 has more room than is available in a steamer.