Heater fan motor service

Details are difficult to remember, a couple photos may help. I recall things seeming delicate.
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You can remove the fan from the box from under the hood. Remove the cover plate against the firewall and you will see the back of the fan held into the heater box. Remove the screws and pull the fan right out. If you need help, I can PM my cell.
 
As Bob correctly says, and very easy. Have done it on all the cars. Cleaning the components and oiling the turning parts will cure any noises other than what is normal.
 
I remember struggling to get the motor and fan assembly out. I’d recommend looking in the blue book to be sure, ahead of attempting this - unless someone with practical experience can weigh in of course.
 
pmansson said:
As Bob correctly says, and very easy. Have done it on all the cars. Cleaning the components and oiling the turning parts will cure any noises other than what is normal.
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Thanks for all the help.
Removal was quite easy but the "squirrel cage" fan assembly seems pretty tight. I lubricated it as best I could but it is still not exactly free spinning. Before I proceed further with more disassembly, I'm curious as to whether or not I should be expecting the blower fan to spin freely or if some "tightness" is normal.

Thoughts and additional feedback is welcome.
 
I don't know exactly how to answer your question, but the brushes within the motor remain in continuous contact with the commutator, and there are springs pressing the brushes lightly into the commutator, so there will always be some friction when you spin the motor.
 
I think a good way to test is run it to make sure it starts right up with no hesitation and when you stop it, it should continue for a bit. If when you stop the power to it, it stops on a dime, then it's still hanging up.
 
Laldog said:
Thanks for all the help.
Removal was quite easy but the "squirrel cage" fan assembly seems pretty tight. I lubricated it as best I could but it is still not exactly free spinning. Before I proceed further with more disassembly, I'm curious as to whether or not I should be expecting the blower fan to spin freely or if some "tightness" is normal.

Thoughts and additional feedback is welcome.
Click to expand...
After my rebuild, the cage spins quite freely, the only hesitation I feel is coming from the magnets, the carbon brushes and a little loss from the bearings. If given a good spin, the cage will keep spinning for at least 3-4 seconds.

The motor itself also has bearings, which could go bad. After all they are in the 'open air', and can accumulate all kinds of dust. However i think they can only be replaced by opening the steel, press fitted motor assembly, and I'm not sure if it could be reassembled again. (requires bending metal tabs twice)

Here the carbon brushes, at the bottom of the pic near the red part:
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You could test easily: Release the carbon brushes and spin the cage; if you still feel hesitations beyond your expectation, then it may be needed to replace the bearings.
Or search for a new motor; Bosch used to sell them back in 2021 (~85 euro, part number is Bosch 0130007002 (info Sept 2021)

you can also tap out the motor from the white cage. In my car it was very tight press fit, and required a surprisingly big whack with a hammer.
This will allow you to clean it all, but more importantly; this is necessary IF you decide to replace the motor.
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You can find a motor repair and rewinding service close by if it comes to that.
 
Hi laldog
I thought my motor was not working also.
I had it out on the bench and connected up 12volts dc directly to the 2 copper terminals and my fan would not spin.

I then investigated it a bit further by using the continuity setting on my multimeter.
And I could not get a reading between one of the copper connections and the carbon brush itself.
I couldn’t figure it out for a while why or how that could be happening but I eventually spotted corrosion on the end of the copper wire that is held against the carbon brush by spring force.
I then carefully took out the carbon brush and cleaned off any corrosion and put it all back together thankfully my motor came back to life.
It was not dead , it had sat unused for so long that the corrosion had built up on the connection between the carbon and the copper.
If you check again, you might get lucky, just like I did.
 

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