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Removing a Blower Motor
I’ve seen a lot of guys recently who reach for the motor puller tool first thing when attempting to remove a blower motor from a wheel/fan blade. Motor puller tools are an awesome backup tool when needed, but using a motor puller tool shouldn’t be the go-to method of removing a motor.
The main issue with using a motor puller for every single motor is its tendency to bulge out the shaft. Motor pullers work by clamping down on a hub and then twisting a small shaft against the motor shaft to push/pull the motor and wheel away from each other. Sometimes, when technicians don’t sand down a shaft and spray the area with WD-40 or other water displacement lubricants, the shaft will get stuck. A tremendous amount of force is required to crank the motor puller shaft against the motor's shaft. These opposing forces can significantly bulge the motor shaft. If the technician successfully removes the motor that way, they often find it more difficult to get the motor shaft back inside the wheel's bore.
I hope that every technician reading this understands that the cardinal rule of removing a motor is never to use any of the following methods:
- Use a hammer/wrench/blunt object to beat the shaft out of the assembly
- Use channel locks of set screws
- Use channel locks on the motor shaft
- Over-tighten the set screw
Any of the above-mentioned sins can result in expensive problems.
Please note the two things that must be completed before using a motor puller: sanding the shaft and lubrication. Guess what…
That’s all you need to do to remove a shaft!
- Sand the motor shaft until shiny and smooth.
- Spray with water displacement lubricant.
- Loosen the set screw (but don’t remove it; they are easy to lose).
- (Optional) Take an adjustable wrench and gently turn the shaft independently of the wheel.
- (Optional) Slightly push the wheel down the shaft to sand the portion of the previously unreachable shaft, which may have a lip that needs to be sanded down.
- Gravity is your friend. Let the motor fall out of the assembly. A shake or two may be required.
Voila! Those are steps a technician needs to do before using a motor puller, yet 90% of the time, those steps are all that’s needed to do the job.
One extra tip: Blow off the sandpaper/rust debris before applying the lubricant, and don’t apply lubricant before you sand the shaft. The debris can get stuck and make things even more difficult, and sandpaper saturated in WD-40 doesn’t do much good.
For a video on this method, we shared a post by Brad Hicks earlier this year of him demonstrating how it's done!
Instead of using an adjustable wrench to work the shaft loose, I use a piece of copper tubing maybe an inch long and a diameter a little bigger than the shaft, slice it lengthwise, slide it over the shaft end and use vise grips on copper to grip shaft to work loose. Never damaged one yet.