New Heater Blower Motor and Cages Scraping

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timteague
Posts: 19
Joined: Mon Feb 07, 2022 1:08 am
Location: Tennessee (TN)

New Heater Blower Motor and Cages Scraping

Post by timteague »

I recently purchased a new heater blower motor with cages to replace the burned out one on my '86 e24. Each time I try to install the motor, upon testing, the cages will rub after I clamp the motor down. There is only one true position that the tabs on the carriage allow for but I have tried every possible position. If I pull the motor and cages out and apply power they are quiet as a mouse. I have not seen any posts about this and am curious if I am missing something. The rubbing occurs even before I attempt to put the top covers on Thanks!
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anchored
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Location: Atlanta

Re: New Heater Blower Motor and Cages Scraping

Post by anchored »

are they rubbing on the top or the sides?
SHRKATK - Red 87' 635csi
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Stoffie
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Re: New Heater Blower Motor and Cages Scraping

Post by Stoffie »

Similar issue here but have not gotten around to taking it all apart yet.

Definitely following this thread!
The M88/3 was all about power, no cats. At idle the raw fuel from the exhaust will make your eyes water like an old V-8 powered muscle car's exhaust did.
TimU
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Location: Sydney

Re: New Heater Blower Motor and Cages Scraping

Post by TimU »

If they are rubbing on the outside edge of the white squirrel wheel blower cages (furthest from the blower motor), then the most likely reason is that the cages are very slightly too far apart and are rubbing somewhere on the black plastic shrouding.

You're going to need to gently tap the cage down the shaft so it's closer to the motor body.
The cages are held onto the smooth-bore shaft by friction only. There is no mechanical attachment.

Try and determine which cage is rubbing: left or right?

Take the blower motor out again and stand it vertically on a solid work platform.
Mark both cage locations on the shaft with a permanent marker, so you can see how far they move in the next step.

Place a flat piece of wood to protect the top of the cage and to distribute the hammer force evenly.
Gently tap the wood with a hammer to push the cage very slightly down the shaft. The cages can be brittle if they're old, so be gentle.
Inspect both shaft markers regularly to make sure the correct cage is moving the distance you want.

Repeat until the cage moves the distance you want.

Reinstall back into the car and test it out.
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Jlc
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Re: New Heater Blower Motor and Cages Scraping

Post by Jlc »

You can try putting a very thing coating of toothpaste gel on the cage to see where tI is rubbing.
85 635CSi Bronzit
timteague
Posts: 19
Joined: Mon Feb 07, 2022 1:08 am
Location: Tennessee (TN)

Re: New Heater Blower Motor and Cages Scraping

Post by timteague »

Sorry for late reply. Discovered there was a small tab on the edge of the seating plastic that helped keep the motor correctly positioned. I was able to place a couple of layers of cloth in the cradle to bring the motor up high enough to spin perfectly without scraping. Now I will see how long that cloth lasts!
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