Blower motor, climate control, temp fixes, brushes

[SJ]

According to its pre-ordained schedule (140k miles), my climate control
blower motor went on the fritz. Sometimes it works, sometimes it dont, it
works after going over a bump, stops at the next bump . .etc etc etc.

The problem is worn out brushes in the blower motor.
Someone mentioned removing the rubber ventilation hose from the motor and
pressing down on the brush to get the motor to work again. I tried it, it
works.

But, I went a step further. Using a dental pick and flashlight, you can
manipulate the brush and its braid power feed.
I also sprayed WD-40 on the brush and its holder to get rid of some of the
congealed carbon dust that was preventing the brush from moving in its cage.
The motor has two brushes. The other brush is at the bottom and cannot be
reached. However, the WD-40 will drip its way around the commutator and drip
down on the hidden brush and clean it.
After spraying, I ran the motor to clean the commutator.
Then I used my hot air gun to blow hot air down the vent hole and evaporate
any solvents remaining.

The blower has been working fine now for 2 days. I want this fix to last
till spring at which time I will put in a new or rebuilt blower.

I have an old blower motor which was replaced on another Audi 2 years ago.
I've been playing with it to see if it can be repaired.
- taking off the plastic cover at the end of the motor is easy. Only two
tabs hold that in place
- removing the brushes is easy. Pry open the tops of the brush cages and out
come the brushes
- unsoldering the brush power braids is a bit more difficult as there is a
crimped rivet involved. Using solder wick and long nosed pliers, I got both
brushes unsoldered in a few minutes.

The brush size is  .310 X .310 X .750   inches. Closest fractional size
would be 5/16 X 5/16 X 3/4 .
I'm guessing at the length of the brushes, but 3/4" should be close. Any
extra brush material can be readily sanded to fit.
The braid length is 1.125" . . longer would be fine.
The braid exits the brush at the top. A side exit near the top would also
work.

The commutator is worn with a groove down its center, but there appears to
be at least another 150k miles worth of copper remaining.

The only trick is getting new brushes. I went to 2 alternator/starter
rebuilding businesses. They dont have anything close. Most of the brushes
they have have thick braids.
Someone mentioned Home Depot's electric tool department - -- they dont have
any repair parts and never did. Same for Leows.
I tried a search on the net and came up emptyhanded.

The best bet for the brushes would be an electric hand tool repair business,
or an electric motor repair business. Hand tool brushes should be close in
size to the blower brushes. You can find brushes on the Skil website, but
you need to give them a tool model number and they give you the brush part
number. I could not find a catalog that had brushes listed by dimensions.

I think installing new brushes would be a quick and cheap fix. If you have
the brushes on hand before the job starts, it only takes 15 minutes tops to
put in new brushes. The lowest price I found for new Audi blower motors is
$100.

Does anyone have a source or contact for carbon brushes?
Has anyone replaced the brushes and can give us some BTDT?


SJ
85 Dodge PU, D-250, 318, auto
85 Audi 4k - - sold but still on the road
88 Audi 5kq
90 Audi 100q