Electric Motor Bushing Lubricant Suggestions?

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I'm wondering if there is a special lube for this application? Emphasis on bushing, as in bronze bushings, not bearings.

Motors I've disassembled had a sort of cloth or fuzzy wick/cotton packed inside that seemed to hold the original lube from the factory. Anyone know what they originally used?

Since the motor-in-question drives a squirell cage blower in a HVAC indoor air handler, I wonder what the techs use or if there's something better?

I noticed some of these motors have external capped ports to oil them while others do not. So to get inside, I'd need to pull the blower cage, remove one side of the housing, remove the squirrel cage from the motor shaft, unbolt the motor from the blower housing, split the motor case and remove the rotor. Just a bit more work than actually replacing the motor itself, but a little lube here could extend the life of the motor and save me ~ $125.

Any suggestions? Any mixologists out there? Lube engineers?
 
I just finished cleaning/oiling a little table fan with 3 in 1 Brand Electric Motor Oil. I have used Rem-oil and Hoppes oil in the past but recently "splurged" and spent the $3 for this stuff. It has blue on the bottle and can be found at the big box home improvement places. These types of things usually specify non-detergent oil and I got this stuff to avoid the teflon in the Rem-oil.
 
I use 3-in-1 SAE20 oil on motors that are 1/2hp or less, SAE30 (no detergent) on anything over.

for HVAC motor with lubable bushings, just form a routine of putting 2 to 3 drops on each end once before the beginning of the winter season, and once after the end of winter season.

It'll hold up for many, many years of service.

Q.
 
The bearing on our forced draft furnace was making some noise a few months ago. I took the motor out of it, and dis-assembled the motor. The plates on the sides that hold the bearing were too hard to get the bearings out of. I had some GC in a bottle left over from changing the oil on one of the gen-sets. I put the side plate on a very flat (ground flat to a mirror surface) piece of steel, but a very flat anything like a glass would work, and poured GC into the center of the bearing, moved the bearing as much as I could with a finger, and let it sit for a few minutes to work its way into the cloth around the bearing. Since GC is a 0W-30 it flows well, but is stout enough for this application. Wipe dry with paper towels, and re-assemble.

Put the flat plate on some old newspaper laying in the laundry tub to soak up any oil.

I did both bearings even though the one on the squirrel cage mount side was obvious the problem because of the large amount of stress on it. I would of liked to swap the bearing to put the one on the sealed off side on the side handling the load of the squirrel cage, but could not get them out.

The motor made a little noise for a few days until the GC oil worked its magic of lubing while any scored area of the bearings eventually cleaned up and smoothed out. A month ago it did make a few noises one day, but it has been running fine now.

So GC saved us the cost of a new blower motor.
 
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Thanks for all the suggestions guys! I thought 3in1 type oils would be too thin so I next thought of something heavier. This horizontal motor is now 22yrs old and runs regularly day & night, due to the long Summer heat.

I remove the blower every year to clean the blades, be sure the shaft freely turns and vac any dust/lint off, but haven't 'split-the-case' for a thorough lube and cleaning. I did recently replace the start capacitor as it was 30% low & out of tolerance.

ND 30wt sounds good. I also have some "Arcopac 90" I forgot about which I use for lubing a sewing machine and in my 30yr old ceiling fans. I think it's straight mineral oil: Crystal clear, no smell, never gums up.

I like the zoom oiler concept. I may have to employ such a device depending on whether I can get to the bushing wick or not. So far I haven't seen any bushing lube ports. Would be great if I could lube it externally without having to split-the-case. We'll see.
 
Split the case and put the sides on a flat piece of glass or steel and do use GC as the oil. GC flows well being a 0W and the special molecules to give it the 30 hold up under stress and heat.

Probably the best oil for this application is GC.
 
Zoom Spout Turbine oil, Ace Hardware sells it, cheap too.

I have a small electric fan used in the summer. With the heavier ND and various penetrating oils it would always gum up and slow down soon afterward.

Lubed the bushings with the Zoom Spout and it ran great the rest of the season.
 
I have a small cheap boxer fan I run at night to block outside noise. As it got older, I was having to lube it about every two months trying WD-40, 3 in 1 oil, and various other oils and sprays. I lubed it last year with a few drops of Amsoil synthetic ATF and it's been running ever since. I would have to recommend a synthetic ATF. It doesn't seem to evaporate or gum up like other oils.
 
Originally Posted By: JimPghPA
Split the case and put the sides on a flat piece of glass or steel and do use GC as the oil. GC flows well being a 0W and the special molecules to give it the 30 hold up under stress and heat.

Probably the best oil for this application is GC.


M1 0w40 is another good choice, that's what I use.
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Quote:
I did both bearings even though the one on the squirrel cage mount side was obvious the problem because of the large amount of stress on it. I would of liked to swap the bearing to put the one on the sealed off side on the side handling the load of the squirrel cage, but could not get them out.

Any difficulty getting the cage off? The way mine is designed there's nothing to attach a puller to should one be necessary. Maybe time for an ATF/Acetone cocktail. Once I get the cage off, I can polish the shaft and coat with T9.

IMG_6740_zps002f5db5.jpg
 
Just a thought, I wouldn't forget the possibility of drilling a small access hole to lubricate the bearings. We have an old over-the-stove blower where the bearings gummed up. I couldn't get enough oil in the sleeve bearing for it to work for very long. So I drilled a small hole in the bearing straps to apply oil to the wicking material. I think I used my 3-In-One electric motor oil. It's been running fine for several years now. I suppose you could even drill a small hole in a blower wheel to gain access where the wheel is press fit on.
 
Originally Posted By: EricG
Yep, Many HVAC techs use Zoom Spout. The spout is to reach tose hard to reach oil holes in fan motors etc!
http://www.lowes.com/pd_188673-13579-5714_0__?productId=3092819

BTY, I refill mine with Mobil One PCMO. LOL
I've been using M - 1 in my TACO circulators for years and also on blower bearings on window AC units. The reason they like "ND" oil is because in wet conditions the oil is less inclined to foam up. I haven't noticed a problem with foaming.
 
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Originally Posted By: pcoxe
I have a small cheap boxer fan I run at night to block outside noise. As it got older, I was having to lube it about every two months trying WD-40, 3 in 1 oil, and various other oils and sprays. I lubed it last year with a few drops of Amsoil synthetic ATF and it's been running ever since. I would have to recommend a synthetic ATF. It doesn't seem to evaporate or gum up like other oils.


Your sintered bronze bushings probably gummed up (the pores) over many years of service. The proper way to deal with this (if you really want to make it last) is to take apart the motor bushings and soak them in solvents overnite to loosen the gum, dry them and then relube with proper oil.

Q.
 
Lately, the heat has been on too much to remove the blower, pull the cage, motor, etc.

The shaft does spin freely with no noise, which is a good thing. It's on my list....
 
UPDATE:
I have a large floor-standing Vornado fan I purchased at a garage sale several years ago. I noticed it would no longer spin-on-start without assistance.

At first, I pointed it straight up, removed the blade and soaked the small gap between the shaft & upper bushing with oil, then let it sit overnight. Made little difference.

So I pulled the motor, split the case and drilled out the 6 rivets holding the two bushing pads in place. They were quite dry and the packing just crumbled. I replaced the packing with cotton pads and soaked both bushings in paint thinner, then scrubbed the inner bore with a .38 caliber brass pistol brush. Followed up by polishing both shafts. Reassembled the bushing pads with small screws & lockwashers & nuts to keep it all together. Then took a small syringe loaded with M1 10w-30 and soaked both pads till they were full. Left them face up on the bench overnight.

Next day, I added more oil to fill them up, reassembled the motor and spun it by hand...incredibly smoooooth and it slowly spun down to a smooth stop.

Plugged the fan in and she's just like new!

I have another medium-sized Vornado floor fan that I plan on giving the same treatment to as it's seen a lot of use over the years though it's not as old as the one above.
 
yes, I found that synthetic engine oil works a long time. I think this is due to it not carbonizing. Synthetics carbonize at higher temps than regular oil.

Oil your computer fans with synthetic. Bathroom fans etc...
 
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