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Discussion Starter · #4 ·
Funny thing is the bearings are sealed an someone put zerks in and the grease just went everywhere but where it needed to be!
 

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I've seen that many times on dairy farms. It's worse on single phase motors as the start switch and rotating mechanism get gummed up. I always suggest one or two pumps once a year.
 

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We had the same problem back when I worked at places that had "crews" of lubrication guys.

One place had a 7 man crew, and thats all they did. It would be fine and dandy if they would have had a way to know what each other had done, but that was not how it was.

So the same bearings often got greased 3-4 times, and that really hard to get at places got zero.
 

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Lol, I may use those pictures in a lecture I give periodically on proper motor maintenance. Over greasing is a really common problem, partly because of the general attitude that "if a little is good, a lot must be better". Somewhere I had pictures similar to that where a user installed an automatic greasing system then decided, without consultation, that a tiny squirt 4 times a year was "stupid" and set it to once per day before the first shift. The excess grease eventually picked up a lot of dust and cooked into a nearly solid mass that eventually lead to overloading of the motor. That happened in just a couple of months.
 

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Funny thing is the bearings are sealed an someone put zerks in and the grease just went everywhere but where it needed to be!
The bearings were probably replaces at one time with double shielded bearing. They should've removed the grease fittings.
It looks like a decent motor, but not TOTL. Sheet metal housing and machine wound stator. :rolleyes:
 

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I have dealt with overly lubricated motors (and the people who lubricated them) that looked exactly like that when removed for failure. I had four 250 HP, 4160 VAC air compressor motors ALL fail within three months of each other due to over-lubrication. The guys just figured that since the motor was so large, about a tube per bearing would suffice (glad I wasn't working there for the majority of this thinking). I was told that they did this routine close to quarterly. That these motors lasted for a couple years was testement to their toughness. But they eventually drowned.

There are some great references out there for motor lubrication. These two links are just a couple that I printed and re-trained my people with.

http://www.reliabilityweb.com/art04/greasing_electric_motors.pdf

http://www.mobilindustrial.com/ind/english/files/tt-electric-motor-bearing-lubrication-guide.pdf

It's amazing how little grease most motor bearings need. There are some high heat, and probably a few other exceptions, but by in large, you should stick with the lubrication programs (+,-) as listed in the above links.
 

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No it's not, there is still plenty of room in there.
:thumbup: The grease is supposed to lubricate the space between the rotor and stator, obviously.

Wasn't till I started doing plant work that I had any idea that over-greasing was even a thing. Our shop guys did a neat demo where they had me run IR on a pillow-block bearing under load while someone just kept pumping grease into it. After they reached a critical point, the temperature began to rise pretty rapidly.
 

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Discussion Starter · #12 ·
Galt said:
I've seen that many times on dairy farms. It's worse on single phase motors as the start switch and rotating mechanism get gummed up. I always suggest one or two pumps once a year.
Our mech maint guys do most pms... Work order says 5 shots weekly.... Lmfao... We got the answer" well, thats how weve always done it!" When we questioned... Smh
 

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Discussion Starter · #13 ·
JRaef said:
Lol, I may use those pictures in a lecture I give periodically on proper motor maintenance. Over greasing is a really common problem, partly because of the general attitude that "if a little is good, a lot must be better". Somewhere I had pictures similar to that where a user installed an automatic greasing system then decided, without consultation, that a tiny squirt 4 times a year was "stupid" and set it to once per day before the first shift. The excess grease eventually picked up a lot of dust and cooked into a nearly solid mass that eventually lead to overloading of the motor. That happened in just a couple of months.
Thats why it was replaced... One helluva noise, yet bearings were good!... Noise was electrical in nature.. Could hear it over the pump it was coupled to.


Hmmmm, wonder what the other 3 pumps look like?
 

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Over greasing is definitely not a good thing. I worked one place where they wanted me to grease everything so much that you could see grease coming out somewhere. The problem I could not get them to understand is that it would ruin the seals and just make it so you had to grease more often and would fail quicker.
 
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