View original topic: R and R on a front blower motor Page: 1, 2, 3  Next
Captain Pike Sun Feb 17, 2008 11:54 am

If your ever so motivated to rebuild your blower here is a quick how to.
I assume your talanted enough to get this far.
The guts of the motor

With vice grips pry the bearing assembly away from the body of the motor. Remove the springs from the brushes,be careful not to streach the springs like I did. Remove the brush assembly and finally the windings.
Clean the contact points for the brushes. Polish the bearing shafts. Blast it clean with brake/electric motor cleaner.

Install the bearing held with the spring metal retainer and molly grease(not too much)
The mag C clip holds the magnets in place
Lightly grease the shafts and reassemble. Secure the 2 spots where you pried off the mearing assembly

:D Thanks to Loogy for shrinking my photos to fit the gallery :D
Next up_______Diesel Starter[/img]

Vanagon Nut Sun Feb 17, 2008 6:28 pm

Hey neat "how to".

Did you replace the bearings? If so where did you find them?

Or was this basically a clean and lube affair?

Looks like nice rainy day job..... I have my old one somewhere in the basement.


Perales Sun Feb 17, 2008 6:35 pm

This is a very clear and simple tutorial. It would be very useful to develop similar tutorials for common issues. Clear photos, with step by step instructions. It takes away the mystery and gives confidence to those of us who need it. We are not all 10 cent dogpilots so any help like this empowers us all. Thanks

Lanval Sun Feb 17, 2008 6:39 pm

I agree ~ excellent work here. Sticky, please. Subject = 'tutorials'



r39o Sun Feb 17, 2008 7:05 pm

Why did you take the magnets out?

Captain Pike Sun Feb 17, 2008 8:39 pm

r39o wrote: Why did you take the magnets out?
Check for cracks. cracks= junk
The mangnets are loose without the clip. I removed them to clean the housing.
Never hit a electric motor with a hammer to "free it of stuck bearings" you crack the magnet_you kill the mag field,no more motor.

Raynor Shine Sun Feb 17, 2008 8:46 pm

this is very cool> thanks for the details

tds3pete Mon Feb 18, 2008 9:12 am

Nice job on this tutorial.

The same basic process can be used to rebuild the starter, just add the step of lubing and cleaning the solenoid. I have fixed several lazy starters on VW's this way.

Tristar Eric Mon Feb 18, 2008 9:47 am

Now tell them how difficult it was getting to the motor! :lol:

I'm wodering if there is a sealed bearing that could be used in place of that bushing?

Volksaholic Mon Feb 18, 2008 10:01 am

Good writeup. One thing I used to do on old air cooled started motors was level and clean up the commutator ring (copper pads that the brushes contact) by chucking the armature on my lathe. I would run some fine emery cloth backed up with a piece of hardwood gently over the spinning ring. You could do the same thing with a drill press. Don't remove any more copper than necessary to level the surface. If you can replace the brushes it gives you back the original surface area for the brushes to contact and I think it reduces the arcing that trashes the commutator ring.

tencentlife Wed Sep 02, 2009 1:27 pm

Yeah, this is good stuff. Often you can do nearly as good as new and save a lot of money (and time waiting on parts deliveries) by refurbing the parts you already have, if you're not afraid to tear into them. I can't count how many relays, controllers, distributors, etc. I've kept in service just by cleaning up contactors, adjusting springs, repairing solder joints or cracked circuit boards, etc. This is also the best way to learn more about how things work. Merely lubing motor bearings, cleaning up/resurfacing commutator, and putting in new brushes makes most DC motors good to go for years more service (since those are the parts that actually wear out). This is a great guide for those who haven't tackled one.

I replaced my front heater fan this year, which had started squealing ages ago but I had kept that at bay by annual lubing of the tail bearing thru the left defroster vent ( an awkward little 5-minute procedure). Finally I had other reasons to get into the dash so I had some time and took the plunge. I even had a refurbished spare junkyard motor waiting in a box for this very day.

I knew from experience, and from examining my spare motor, that it's the tail bearing that gets the worst wear; the one at the fan hub is near the fan's center of gravity so is under a fraction of the stress. The tail bearing also gets plastered with dust from the incoming airflow, while the hub bearing is better protected from that. So if you can keep lube in the tail bearing, and dust out, the motor will run quiet for a long long time. While I still had the whole airbox on the bench I added a little mod (it was actually Reiney's idea ) that covers the bearing and lets me easily add a couple drops of oil to it periodically:

It's just a plastic hole plug, with a drip irrigation nipple inserted in one side. The plug is attached to the end plate of the motor, covering the bearing, with some sealant around the rim and a wire bail to keep it in place. The soft vinyl tubing is routed thru a hole into the left defroster vent, and folded over in there. By popping the louver cover off and dribbling a couple drops of oil down the tube once in awhile, the motor's most-stressed bearing is serviceable. Plus it keeps dust away from it. I already know that oiling that bearing keeps even a squealing motor quiet for years, this just makes that little job easy.

markz2004 Wed Sep 02, 2009 1:33 pm

tencentlife wrote:

I had kept that at bay by annual lubing of the tail bearing thru the left defroster vent ( an awkward little 5-minute procedure).

Can you elaborate please?


tencentlife Thu Sep 03, 2009 7:46 am

You have to drill a 1/2" hole down inside the left defrost vent, in just the right spot, and then you can squeeze your head in above it (this would be a breeze if the windshield weren't there) and see down the hole right to the leftside bearing. By running the fan you can spot the shaft spinning. You can insert a piece of tubing down next to the bearing and dribble some oil down onto it. It fixes the squealing for a year or more, but not easy to do. The hole has to be against the forward edge of the bottom of the vent floor (lift out the louver cover and you'll see what I mean) and about 1 to 1.5" left of the right forward corner.

You can stick a patch of ducttape over the hole afterward, but it's really not large enough to matter.

Not easy, fairly frustrating (unless your head happens to be small or pointed) and not for the faint of heart, but it does work. The tubing mod above does the same thing but makes it easy.

fairweather Thu Oct 15, 2009 5:34 pm

Just installed a new refurbished blower motor (one I had from a parts van) today using these pics as a guide, works great. I didn't take it apart as much but did clean it with brake cleaner and lubed the bearings.

I was able to get to the front bearing by drilling a small hole in the cone shaped plastic on the inside of the squirrel cage and using the red tube from a Tri flow bottle. Spins like a dream now and is way quieter and blows more air than my old one did.

Best part is it didn't cost me a dime, well ok the zip ties I used to clamp the box up cost a few cents.

I also drilled a hole in the metal of the fresh air dam so I can use a tube to spray the outer bearing at any time just by removing the grill (the plastic screen is long gone). I did manage to get the original fan lubed this way but it turned out to be cooked.

polenta911 Thu Feb 03, 2011 5:14 pm

First time poster long time lurker :D

Squealing front heater motor lead me to this thread where it seems the two above people have been able to fix or at least maintain the motor and was wondering if there are any pics. I was thinking instead of drilling a small hole that would be hard to see through why not just use a hole saw so you can see what you are doing then use an electrical plug or similar to plug the hole?

1" hole saw, flashlight and lube anyone?

joetiger Thu Feb 03, 2011 5:20 pm

Welcome long time lurker.

The Mullendore Port:

polenta911 Thu Feb 03, 2011 5:27 pm

Of course! The Mullendore Port, can't believe that didn't pop into my head when I was searching. :shock: Great name for a beer!

7 pages between two threads on drilling a hole! jackpot!

Now that I have the location of the hole I think I will go bigger.


rubbachicken Wed Oct 26, 2011 6:45 am

is there a nack to getting the fan off of the armature, i don't want to risk breaking it as i don't have a spare

Captain Pike Wed Oct 26, 2011 4:24 pm

Any metal punch will do. Not as bad as you might believe.


The"port" does nothing to the other bearing. Worth a try but only a temp fix.
AND Please do not splooge up this topic with "your" drilling experiences.
The purpose of this post is to inform not to discuss other solutions.
Thank You.

F#@kn bulls%!t sh!t storm this will unleash. Except for Chris, that actually will work

Worms Fri Oct 28, 2011 12:43 am

Is it not easier to buy a new one? Or are you going to tell me they are crap?

I have a new one in my shed, ready to go in - Cost me 25 pounds...

Please tell me they are OK!

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