Need Opinion On How To Disassemble Motor

[benchtech]

Hello all! I'm trying to pull this motor so that I can get at it internally to wire it for 220V. Unfortunately I can't figure out how to get the fan blade off. There seems to be some sort of pin wedged in between the motor shaft and the blade. Does that need to be removed to get it off, if so how?

I was hoping someone here has worked with something similar and could point me in the right direction.

TIA!

(photos)

 

[desertfox]

Hi benchtech

That pin you refer to is actually a keyway and the fan and key for that matter might be an interference fit, you could try heating just the hub of the fan blades so that it expands and then it should come off.

desertfox

 

[Skogsgurra]

Hmm...

That "sort of pin wedged in between the motor shaft and the blade" looks very much like an ordinary key.

It is usually quite easy to just pull the fan off the shaft. The locking screw seems to be removed already. If it isn't, then just do it.

Gunnar Englund

http://www.gke.org

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Half full - Half empty? I don't mind. It's what in it that counts.

 

[MikeHalloran]

The circled object is a key. The fan will slide right over it.
... or would, if you have not mangled the end of it too badly.
Is that a chisel mark on the end of it?

What you need now is a pulley puller, that can grip the fan blade hub, and push against the end of the shaft. Some kinds of pullers can engage the groove in the hub adjacent the end for that purpose.

Caution; put a hardened screw in the tapped hole in the end of the shaft before engaging the puller. A typical puller has a pointed screw that will enlarge the end of the shaft while applying the couple tons of force it will take to force the hub off the shaft. The fan will eventually come off anyway, but the enlarged shaft makes it a lot more work, and makes it more difficult to put the fan back on later. Electric motor shafts are usually made of pretty soft steel, and easy to distort.





Mike Halloran
Pembroke Pines, FL, USA

 

[MikeHalloran]

Carefully measure the hub end, and take the photos to your local air conditioning parts supplier; they should have an appropriate puller for sale.



Mike Halloran
Pembroke Pines, FL, USA

 

[ccjersey]

It's very likely you can take off the cover on the opposite end of the motor and access the wiring. I don't know of any motor that is designed to be disassembled to reconnect for different voltages. The connections you need to make should be in an easily accessable connection box somewhere on the motor.

If you must remove the fan, an autoparts store may have a puller that will handle that job. Power steering pumps on cars usually have a similar pulley that can only be pulled with the proper puller (unless you don't mind destroying the pulley)

 

[benchtech]

Thanks for the tips everyone!

"It's very likely you can take off the cover on the opposite end of the motor and access the wiring. I don't know of any motor that is designed to be disassembled to reconnect for different voltages. The connections you need to make should be in an easily accessable connection box somewhere on the motor."

This motor is wired for 110V but does not have a external box that will let you switch it over. I've seen this exact motor made for this unit under other name brands and on all of those models it comes with an external box with terminals to switch between 110v/220V. In the manual it actually shows a diagram how it's wired for 110v with an external terminal box but on the unit itself the box is no longer there. I'm positive the motor can be set up for either or but the company opted out of putting the extra box and terminals most likely to cut down on costs. Also they sell the same model with a 220V only motor that looks identical to others that allow you to switch between 110/220V.

 

[benchtech]

Unfortunately, there's another fan on the other side of the motor that is made of plastic and I can't pull that one either. I assume it's glued on? But I'm afraid to pull hard on it should it break. Even if I were to get that off there's 4 bolts on the side of the main fan housing that can't come off until the main fan blade is removed because they are butted up against the housing.

 

[ScottyUK]

Don't use a pulley puller on that fan, it will just deform and become useless - it looks like it is only 1mm thick, if that. Try a few drops of thin oil or dismantling fluid like 'Plus Gas' dropped down the grub screw hole.

You might be able to get some purchase between the hub of the fan and the motor endbell, but don't use a lot of force otherwise you'll damage the bearing.


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If we learn from our mistakes I'm getting a great education!

 

[MikeHalloran]

It appears that the fan hub is designed for removal using a tool very much like the ones sold in auto parts stores for power steering pumps. ... but perhaps in a different size; it looks a bit larger than the p/s pulleys. But you might borrow or even buy one of those just to see how it's made, so you can knock out one of your own; they're pretty cheap now.

Scotty is right; a regular 'pulley puller', meant to grab a sturdy iron spoke, will just trash the fan.


Mike Halloran
Pembroke Pines, FL, USA

 

[waross]

The tool we used to call a bearing splitter may be able to grab the groove on the hub.

Bill
--------------------
"Why not the best?"
Jimmy Carter

 

[Pumpsonly]

Try tapping the fan hub lightly with a small mallet. If it move in and expose the key, pull out the key with a plier. After that the you should be able to pull out the fan by hand.

Good luck.

 

[starkopete]

Hi,
If you look at the puller in the attachment you can see the collars/hub adapters, these can easily be made. The groove in your fan hub will provide an excellent spot for the bolts to grip. A little heat will help when you go to pull it.

http://www.grainger.com/Grainger/POSI-LOCK-Hub-Puller-Adapter-Set-5LD39

Thanks

 

[MikeHalloran]

A concentrated load, as from radial bolts or a small number of puller jaws, will cause the outer lip of the hub groove to deflect locally and make the hub more difficult to remove.

I have a puller exactly like the one in this video:

http://www.youtube.com/watch?v=r9i1FT-w-JY

It does not need the groove to work.
It does work very well.
The video does not show the witness marks that the setscrews leave on the hub.



The groove is clearly intended for a puller that fully supports it,
like this one:

http://www.amazon.com/Performance-T..._1_cc_2?ie=UTF8&qid=1305654598&sr=1-2-catcorr

Sorry, I could not find a clearer illustration. The tool comprises two half shells with inner radial fins that engage hub grooves, a sleeve to keep the shells from expanding, and a disc and screw that push on the shaft.





Mike Halloran
Pembroke Pines, FL, USA

 

[benchtech]

Any DIY ideas? I'm pulling it once and didn't want to spend a lot of cash finding out that I might not be able to convert it over to 220V.

 

[MikeHalloran]

At least buy a can of AeroKroil.
That and a hammer might be enough; it's good stuff.




Mike Halloran
Pembroke Pines, FL, USA

 

[starkopete]

Hi,
I'm not a big fan of 'miracle' lubricants and such, but Mike H. is right, AeroKroil is an amazing product. It does an excellent job of freeing up metal to metal parts. You will be amazed at how well it works.

Thanks

 

[ccjersey]

If the lubricant doesn't work, then use a quick application of heat to the hub. If you take too long to get it hot, then the shaft will get hot and expand too.