Replacing the broken bearings in my pm1440gs headstock

Cadillac said:
Make sure the oil port for bearings are clear of all metal debris I'm sure you knew that. Might wanna look at putting acouple strong magnets at the bottom.
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Good point about the oil ports, it is also something @TakeDeadAim had mentioned also. There is no oil port, I was thinking there might be, there is a small dimple on the chuck side, but it does not go thru. There is no mark or hole inside the opening for the pulley side either.

What would be the way to approach this? The bearings have hard rubber inserts on each side, I would not call them sealed? I am not very knowledgable on bearings though. 6402-rz are the numbers on the bearing.

Any input, now is the time to make changes if any.
 
If the suffix is RZ,then it has one rubbing (grease) seal,one tin shield ......if RS,then just one rubbing seal (grease) on one side,other open.Generally , only a 2RS bearing will be "lifetime lubricated",(which works OK in oil,because there is a slight oil leak into the balls as the seals wear)...............as to noise ......sometimes Chinese bearings are noisy,very noisy,especially in electric motors at 3600revs......This does not mean they have failed or run dry,because on inspection ,they are OK ,and have plenty of clean grease.Anyway,make up a driver that puts equal pressure against inner and outer races,or the bearing will brinnel.Avoid driving if possible ,and pull the bearing in ............and rolling element dont need much oil,and flood oiling carries dirt and damaging particles into the balls.....If the balls lock on a piece of foreign matter,the cage may break,causing a true failure where the balls fall out and often get jammed in gear teeth.
 
It had looked like on the small gear side there is a hole on top of where the bearing housing is. Was it the bearing behind the larger gear that failed? Could be why it failed no real lubrication?
As for the seals on the bearings. Since it is in bath of oil with really no chance of outside contamination I would pull the seals off both sides or at least the side where the oil can get in easier. Anyway to get more oil there would be beneficial. When you say the bearing has a hard rubber kind of seal is it the ball cage and not a separate seal that can be removed?
 
No on the hole. It's just a dimple on the casting. No thru hole either. The bearings I was sent are 2rz. Which by john.k post means the bearings i have are sealed. I have some work to get the shaft and gears seperated and reinstalled. So i have time to ponder this. Still waiting on a responce from pm. Should be soon.
 
Note that all my offshore bearings in my casting are in good shape. None of them get oil. Mine was bought by me in 1981. So far, so good, the only complaint is my seals. sigh.
 
Thanks for the input dabbler.
Matt says he has ordered me NSK unsealed bearings. He feels it will be better for this application. I'm going to go on his experience with this. My machine is one of the earlier models, I realize this is just the 1440bv and other models with upgrades. I am guessing the factory and matt have seen enough of these at this point to know what is the best.
I removed the linkage, pulled the shaft, cleaned her up and set all the gears back on, except for the 1st 2 gears on the pulley side.... when the bearings get her I'll take a long hard look at her and decide which end goes in first.
Still a ways to go, almost seeing light at the end of the tunnel.
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generally,if you buy a ball bearing at a bearing shop it will be double sealed........if you comment,the counter guy will say "pop the seals out,if you dont want them."......Now ,in a gearbox ,any gearbox,with sliding gears (called crash gears in a car or truck),all the rolling element bearings will have a thin flat steel "chip guard".....this is separate from the bearing,but stops chips from the gears getting into the bearings.....If multiple tiny chips go through a bearing,the rivets holding the cage together will fail,allowing the balls to fall out .This is a common failure in old Norton motorbike gearboxes when the chip shield is left out on reassembly.
 
That would be a shielded bearing. There’s sealed, shielded and open. Sealed is most protected but runs hotter and goes down from there.
 
Yes the thin metal covers are called shields, the rubber ones are seals. Some oem bearings have a shield or seal on one side and open on the other
 
An easy fix is the large magnetic washers fitted in Fuller Roadranger gearboxes.....they are just a thick 2" dia washer magnet that sticks to the cast iron of the transmission and collects any magnetic chips in the oil....they stay put in a truck ,so a lathe wont move them...very effective,and generally look like a black donut at overhaul.
 
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