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Motor bearings

4870 Views 10 Replies 3 Participants Last post by  gottdi
My motor bearings squeal. Have been doing it since the start, but now I'm approaching summer and 10,000 miles. Last summer the motor was getting pretty hot, and I thought it might be time to look at those darn things.

When I first started up the truck, jacked and chocked, I had a runaway condition caused by a Kelly controller. The motor spun the tires up to over the max speed my speedometer goes up to.

So other than squeaking, the thing (Warp 9") works great, holds spinning motion for a while, but not as long as my forklift motor (12")

Do I worry, or wait for more noise?

Thanks,

Brian Mathis
www.evalbum.com/1752
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My motor bearings squeal.....Do I worry, or wait for more noise?
Hi F16,

First off, how can you be sure it is bearing noise? My experience: If you can actually hear a bearing make unusual noise, you'll have catastrophic failure in the near future.

So other than squeaking, the thing (Warp 9") works great, holds spinning motion for a while, but not as long as my forklift motor (12")
The fact that the 12" motor spins longer likely has nothing to do with bearings. I assume you refer to a condition of no-load where you have equal RPM and time the coast down. This is influenced by the rotor inertia, brush friction on the comm, windage (like a fan or rotor shape), bearing lube and seal drag.

If the bearing itself is causing a drag to slow the rotor down in noticeably less time, that bearing would again be destined for catastrophic failure in short order.

Regards,

major
G
Here is my clip of a bad bearing that came out of my GE 9" It did not squeal at all but when I took out the motor it was obvious that the bearing was toast. I replaced it the next day. Turn up the volume to hear. This is a bad bearing from the drive end. I replaced both so now both are new. Bearings don't always squeal if they are bad. Sometimes they just bust. This one had not yet busted but it would not have been much longer. If it busts you will more than likely loose your shaft in the process. Happened this past weekend with our riding lawn mower. A mower blade shaft bearing just blew its guts all over and toasted the shaft. It's now in the shop.

Pete :)

http://www.youtube.com/watch?v=X3T2u1q9SNI
Hey Major,

You've got a point. I just assume its bearing noise from the motor. It makes the noise in or out of gear when motor is spinning. I work at Coc-Cola as a mechanic and have had 20+ years in the Air Force working F-111's and F-16's and I totally agree I should have a failure soon if it were the bearing, but yet it still sounds the same and hasn't blown. I see bad bearings almost every day here at Coke.

I was just comparing motors. My Warp 9" in the truck squeals and slows down faster than the 12" forklift motor I had in the Ford Probe. I would figure the bigger motor would spin longer, was thinking of trying it in the S10, see how that runs on a 1K!

I'll take some video and try my luck at youtubing it here.
Here's mine with a bad bearing:

http://www.youtube.com/watch?v=PfGciqZn4kM

and with a new bearing installed:

http://www.youtube.com/watch?v=rFf9wnWdxaY

both spinning up to 3600 RPM.

JR
Wow, that thing really growls. I guess mine is really nothing so far. I'll try to post video here from you tube. Always have a problem with the links. Tried several different methods...
Here is my clip of a bad bearing.... shaft bearing just blew its guts all over and toasted the shaft. It's now in the shop.

Pete :)

http://www.youtube.com/watch?v=X3T2u1q9SNI

Here's mine, if I get the link right...
MiniBMS... http://www.youtube.com/watch?v=jML8s8c1opI

Squeaking motor... http://www.youtube.com/watch?v=EjPQyuym0Vk

I don't know what I'm doing wrong that the youtube links don't work..
Isn't that squeak coming from that pulling looking thing at the end of the shaft? It even looks like it might be rubbing against the metal bracket. Have you tried shooting it with a squirt of WD-40 to see if it quiets down? Unless your bearings grease is dried up, I can't see how that squeak would be coming from there.

JR
Isn't that squeak coming from that pulling looking thing at the end of the shaft? It even looks like it might be rubbing against the metal bracket. Have you tried shooting it with a squirt of WD-40 to see if it quiets down? Unless your bearings grease is dried up, I can't see how that squeak would be coming from there.

JR
Yeah, after watching Gotti's videos, it doesn't seem like the same type noise. It might still be a bearing, but its nothing serious at the moment. The squeak has been around almost since the begginning and I just went over 10,000 miles today.

The pulling looking thing (white) is just a magnet mount for the tach, the bracket around it holds the sensor, they were installed after the squeak, and are not rubbing against anything.
G
Sounds like a harmonics squeal coming from the motor. The video makes it seem like that pulley but maybe it's a harmonics squeal coming from the motor. My starter/generator motor has a harmonics squeal to it but not quite like that. So maybe like was stated squirt a tiny bit of wd40 and see if it stops. If it does not it may just be harmonics.

Pete :)
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