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Ideas to remove squirrel cage off heater motor?


FBBO Gold Member
FBBO Gold Member
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5:12 AM
Jan 28, 2012
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I thought I had the squeal in my fan motor fixed but testing it today showed that not to be the case so it will need to come apart. My squirrel cage is stuck on good and tight. I wetted it with 50/50 acetone/ATF mix, shimmed under the cage to pull the shaft up in the motor and give me something solid when I rapped on the end of the shaft with a brass punch and small hammer. Nothing yet gives so I decided to let it sit and soak overnight. Yes, the set screw is removed.

Holding the shaft with pair of clamping pliers and trying to rotate the fan on the shaft hasn’t worked yet.

Any other ideas would be appreciated.
IME - letting stuff 'soak' a good day or more has had good results I've used liquid wrench soak, could try using a hair dryer to heat up the blade to create some expansion from the shaft. The gentle shocking you did can help it along. Forcing the desired result being in a rush can give you the...undesired result, lol.
I have a pretty good heat gun. I’ll try dialing it up tomorrow and see if that does the trick.
No, I don't think we mean a little heat like in a hair dryer, we mean a nice oxy-acetylene
torch with a small tip and heat it quickly for about thirty seconds! That'll do it!
No, I don't think we mean a little heat like in a hair dryer, we mean a nice oxy-acetylene
torch with a small tip and heat it quickly for about thirty seconds! That'll do it!
Patience...my motto...my dad tried to teach me after too many knee-jerk errors...lol
Not enough heat to travel up the motor shaft and melt anything, just enough to
expand the squirrel cage fit so it releases from the shaft! You can put an air nozzle
on the shaft to cool it down after trying. Heat it for twenty seconds, then cool it.
Try thirty seconds, then cool it. Heat IS your friend! Just be carefull.
I've seen 2 set screws in the same hole. Not sure what it was on, but you might take a second look at that.
If you can tack weld a nut to the squirrel cage hub? Then you can use a bolt in the nut to push the shaft down and off. Maybe?
Set screw is removed and oil squirted into the hole resulted in oil coming out between the flat in the shaft and the fan hub so only 1 in there. I'll give it another try today.
I’m a big fan of Kroil penetrating oil and keeping it soaked and patience ( something I need more of)

Well, lots of penetrating oil and enough heat to smoke off the oil failed to have much effect. So I cribbed up with wedges between the fan and the housing and basically drove it off. It hung up when it got flush to the fan hub so I had to drill the shaft to thin it out about 3/8 deep to get it through the hub. So saved the fan and heater plate.

After cleaning and lubing the motor it runs OK but I must have shifted the shaft enough in the armature to the point it’s bottoming in the rear bearing cup. Trying to shift it back in a press didn’t look promising so I think the easiest solution is to take a thirty-second off the end of the shaft as the front is plenty long. Hopefully it will outlast me.
At one point driving the shaft off the fan, the cribbing I had under the heater box panel shifted and the back half of the motor dropped into contact with my bench and I think deflected/pushed in the bushing housing on the bottom as I was hammering on the shaft. I think that is why the shaft was bottoming out in the case. I put it on a big PVC coupling to support the outside of the case and a socket inside on the bushing cup and stretched it back out in my hydraulic press. That fixed things and the motor spins freely and is pretty quiet. So it’s back together, doesn’t squeal and seems none the worse for wear at this point.
Good luck!