Can you lubricate sealed bearings?

[608KEB 795]

I was wondering if anyone has greased sealed bearings before. I replaced the old bearings and they still spun freely. Let me know if anyone has done this or had some success with it. I have some needles that would work. Am I just wasting my time?

[skrusins 128]

I have a needle for my grease gun and got a little more life. The only problem is if the bearings are

somewhat damaged from being dry too long. On the rubber seal bearings no problem, but the metal

sealed had to carefully drill a 1/16 hole to insert needle.

[608KEB 795]

Thanks where could I get a needle for my grease gun?

[groundhog47 347]

On the flat roller/ball bearings with rubber/rubber metal seals you can carefully pry out most seals at outer race edge, clean inside ball/cage group, aplly small amount (not overdone) suitable grease(usually Lithium based, grease, some compounds react negatively with the Lithium grease), snap back in seals, and good to go. My spindle assy uses an unsealed top (both sides) bearing and a sealed one side bottom bearing. Bought some spare bottom, had 5 or 6 top and took one seal out of enough to make three sets with no, prob. It can also be done with a vacuum set up but first need to get old grime out and verify "ball" integrity (?feel). On the sealed needle type may be able to create an access hole in the seal (very tight set up), but getting grease to fill that length/space is real iffy. Metal seals, haven't tried removing and replacing seals but have pried up a bit of inner portion to access with hypo needle (14ga) and hope will circulate around (experiment, didn't put to load/rpm test)

 

Oh yes copied idea from internet query.

Edited September 4, 2013 by groundhog47

[SousaKerry 501]

We had a needle rigged up on the farm years ago.  Dad took an inflation needle for a basketball and screwed into a small pipe coupling and a grease zerk in the other end.  He would use a needle till it was no good anymore and just screw in a replacement.  IIRC he cut the end of the needle off with a grinder on a bevel so the end was sharp and would just jamb it under the seal.  Saved many an old bearing on farm implements that way. 

[tunahead72 2,403]

Thanks where could I get a needle for my grease gun?

 

Plews/LubriMatic grease injector needle, part no. 05-037, for all hand grease guns.  I got mine for about $5 at one of my local auto parts dealers.

 

I've only used mine on a couple of mule drive pulleys, and keeping them as spares.  So I don't really know how well these techniques work, but they do feel smoother and quieter when I rotate them by hand.

[skrusins 128]

Any NAPA stores have them on their shelf,.

[jwms 0]

use moly on lots of bearings on industrial print engines. Slip an x-atto fine point under the outter edge of the seal and pry up. run a bead around the one side and press the seal back into place. be careful not to bend the seal when pulling out or pushing it back in. in hi temp apps we use a teflon grease. if you poke the needle thru the seal, you can dimple the seal, it also creates an entry point for the nasty stuff that bearings do not do well with, DIRT AND/OR MOISTURE. not much of a problem in a semi office environment but outside in the field with a plow--WOW.

[timo4352 147]

I just greased the sealed bearings on my snowblower. I really had no idea it was even possible until reading about it here. The needle didn't do much for me, but I was able to easily pop off the seals. I then rinsed them out with spray Seafoam to get the yuck out, and packed them with grease, and popped the seals back on. First time I've tried it and I guess time will tell if it's worth doing or not.

New bearings would've cost around $200 so I'm trying this first.

[ARK 9]

As it happens I just did that to two bearings on my 312-8, Mule drive.  After reading the many posts here I closely examined the bearings after cleaning 24 years of dirt and discovered the shields on both were neoprene.

 

With dental scraping tools for teeth which I use for many projects, I lifted the rubber side off and away cleanly from the bearing.  The bearings were dry, noisy a slight rumble was felt when TURNING SLOWLY BY HAND.  I repacked both bearing from one side, fully packed for the winter storage.  Then with a small screw driver I pressed the rubber shield back into place and slowly ran the flat of the driver over the rubber to verify a firm seat and that all was sealed.

 

In testing the sheaves with a drive they both turn smooth, quiet at very slow and at higher speeds.  Cleaned the mule drive including threads, took apart everything that comes apart, wiped excess grease, cleaned with brake cleaner especially the fat a V sheaves and put away until spring.

 

I have done the same with metal shields while in the trades, but results often leave the shield damaged.

 

I know little history of this 312-8 but I am now the 3rd owner.  The tractor weighs 550 lbs and I think I removed that much dirt, grass, clippings along with carbon, grease, but it runs very very nice and the 44" deck took a day to remove, clean, sharpen , balance, then grease and oil for the winter.  It now sits raised off the floor waiting for spring.

[oldblue1993 98]

I am just throwing this out there becouse I have used the needle or drill hole method a few times, after your done seal the hole with some rtv sealant as the new hole will not only let dirt in but the grease out when its warm.

[tarcoleo 119]

For many years I operated tools requiring shielded ball bearings operating at 11,000 rpm.
These bearing were small, approx 3/8"x 1".  Their life was extended many times simply by
cleaning them thoroughly with  agitation in solvent, then relubricating them in another
solution of grease dissolved in lacquer thinner.  Shielded bearings are not sealed.

[swarfeater 49]

I have a small cast iron pot with grease in it that i use for regreasing bearings. i put it on a camping stove outside  cold with bearings packed down in the grease and turn the stove on. let it go on med heat untill the grease heats as far as it will go without burning, then turn it off.. while heating the air in the bearing expands and escapes, while cooling the remaining air contracts and sucks the grease inside.  just leave the bearing in the grease untill cool, i usually repeat the process (only takes 10 mins to heat) twice. done it for many years, works pretty well.