To grease or not to grease, that is the question...

[Alastair]

Over the years have been reading on here avidly, and have picked up many great tips, one which I would like to debate. This is the re-packing of bearings.

Many great people on Bowl-tech have talked of doing this practice. I personally am a little unsure of it. We have tried re-packing some bearings, from PBL to ratchet, with copper grease. (An anti-seize compound used to reduce brake squeal)
I find that once the seal has been popped of and the bearing filled up with grease and replaced, after a short while the grease will ooze out of the seal, and on occasion the seal will pop off.

Do you think that this practice is worth while??
Is there not enough grease already inside of a bearing to last its life span?
Let’s consider the rear roller, or front roller bearings.
A topic of late where they were talking of these said that at the rpm of the bearing, even with no grease the bearing should last least two years before failure. With grease in them, then should last for a long time.

I have also come across a fact which I am most surprised about! Did you know that AMF charge more for the PBL ball bearing with out the D than they do for the D style one. Why??
I have been persuaded off of the D-style bearing and rod for the PBL, with good reason. The rod wears quickly as the bearing is pulling on one little edge of the rod. In the space of two weeks you can remove the rod and find a large amount of wear on the shaft. The D style bearings seem to last for a shorter period of time also.
Could this be like the Beet Amax vs. VHS scenario? VHS is not the superior product but just marketed better, so taking over?

The anti-seize grease is good for:-
- clutch pinions
- Rear roller end where pulley attaches
- Splines on gearboxes

anything else may not be cost effective.

[BowlEquip]

Re: To grease or not to grease, that is the question...

One point to remember is that the manufacturer of equipment usually specifies to the bearing manufacture the amount of grease (fill rate) to be packed into a bearing. This usually is determined by SPEED, LONGEVITY OF USE, and PRESSURE. Bearings are almost NEVER completely filled/packed as we are used to doing it. 100% fill of grease will result in oozing and popping of seals.

The distributor/kicker and pit roller ball bearings are notorious for seals coming off. These bearings are always turning while the back ends are on. These bearings I usually replace when rebuilding.

However, 190 001 490 bearings used in the Table Yoke only pivot 90 degrees once every frame. They are also used in the table drive clevis where they rotate even less. These I clean out completely and repack to 80% fill, both sides.

Bearing in the Table Drive Clevis rod end make one revolution every run of the table, but have a lot of pressure on them. Don't worry about seals popping off, since there is a gap between the two within the rod end. I fill these 100%.

You get the idea [img]/content/btubb/images/%%GRAEMLIN_URL%%/wink.gif[/img]

By the way, those who have SurePiks: same bearing as the yokes. For this use, I would always go with new. Save the good old used ones for the yoke & clevis!

[bent wrench]

Re: To grease or not to grease, that is the question...

For the cost of bearings ... I just replace. Plain and simple.

[8270king]

Re: To grease or not to grease, that is the question...

Not only do you need to repack bearings, you need to wash the transport grease out of new bearings and repack them before the 1st use.

[Tablejam]

Re: To grease or not to grease, that is the question...

The D shaft does not spin inside the bearing and wear itself down to nothing like the round ones do. This is true for both the upper and lower shafts/bearings. We do not use the round ones for this reason. Every lift of ours that has had the round ones on it had to be replaced with the'D's because they were no longer usable or there was too much slop between the shaft and bearing. D shafts and bearings can and will last a long time, I dare say longer than the round ones.

[amf8270mp]

Re: To grease or not to grease, that is the question...

We had alot of ball lift bearing failure before I started repacking the bearings.ALOT less failure since I started repacking them.

[TheGMan143]

Re: To grease or not to grease, that is the question...

Originally posted by 82/30 king:
Not only do you need to repack bearings, you need to wash the transport grease out of new bearings and repack them before the 1st use.

<font size="2" face="Verdana, Helvetica, sans-serif">You got it, King... with the exception of "sealed" bearings, they do need to be repacked. The grease they are shipped with is lighter and has more rust/corrosion preventive properties for storage (to keep them shiny and looking new) than it does lubrication qualities for running the bearing under load. Most times, the grease that they are packed with will melt and drip out as soon as they heat up a little, leaving the bearing with very little lubrication.

[Kingram]

Re: To grease or not to grease, that is the question...

Had a bearing salesman to tell me once that you could cook with the grease that most bearing companies pack new bearings. He said that most pack with a hydrogenated cottonseed or linseed oil (I call it ear wax). Whether that is true or not, we always clean and repack ALL new bearings out of the box. Have been doing this for about 30 years and have even had some bearings to last that long (if you repack about every five years).

We repack 100% and all excess will be pushed out. Have had very few seals to pop out after this procedure. If the seal bends while being removed just squeeze it back into shape with needle nose pliers.

Shielded bearings (seals that cannot be removed without destroying) are usually packed with a very good grease and will last several years. We also repack some shielded bearings but it is a longer process. Have to drill a small hole in the shield and it takes many soakings and running on the wirewheel to sling all the old grease out of it. Inject new grrease in and then reseal the small hole with a dab of JB weld.

[JimDorsin]

Re: To grease or not to grease, that is the question...

I have actualy taken a pair of lanes and use the front roller bearings stock on 1 lane, and repacked the other. 2 years later, not a problem with either.

I agree with G. The sealed bearings need not be repacked, as 90% of our aplication is very slow moving.

(If I were puting them on my cars spindel, and driving my kids around town, I might feel differently. The speed just dosent create enough friction in ball lifts and front/rear rollers)

I have had yet to receive table eccentric bearings pre greesed. (I do, however, find most of my outer dist. clutch plates are oiled....lol I assume to protect form corosion. One place you hate to see oil, and it comes there factory installed...lol)

[Alastair]

Re: To grease or not to grease, that is the question...

A lot of the bearings we use are packed with blue grease. Well, when I say grease it is more like a gel. It seems to be some kind of polymer gel with perhaps some water resistant qualities??

Which bearings do you receive that are not sealed??

No one has been so brave (minus tablejam) to comment on the D shaft and bearing comment.
A point I could add to this, which is slightly on the same vain, is that of the super clutch. I noticed today that on cleaning maintenance, that the super clutch metal plate has cut into the dizzy shaft quite badly, just like the D style bearings cut into the D style shaft!

[8270king]

Re: To grease or not to grease, that is the question...

Originally posted by JimDorsin:
(If I were puting them on my cars spindel, and driving my kids around town, I might feel differently. The speed just dosent create enough friction in ball lifts and front/rear rollers)

<font size="2" face="Verdana, Helvetica, sans-serif">Your position is that a ball lift rpm rate is so slow that bearings do not heat up?

I think ball lift bearings require washing and re-packing as normal PM.

[JimDorsin]

Re: To grease or not to grease, that is the question...

well, I have slowed down my ball lifts in every house that hadent already (5 inch pulleys)

I can see how the 3 inchers would require a better lubricant than the 5.

What I will commit to, is that in 18 years, I have had no more or less problems using them with the stock lube than I had in vermont. The guy (he went by Shaw here on BT) that was hired to do summer maintaince b4 I started was heavy into repacking. He did every pit bearing, and every ball lift bearing in the house. over 3 years, I think I blew out 2 lifts.

I have never had a roller bearing go. I do, however, pull and inspect them every year (as well as the lifts) and replace if the seals are not intact, or if the bearing does not turn smoothly.

My hats off to those that actualy do re-pack them, I dont see the need, but the dedication is admirable. (bear in mind, my other duties over the last 10 years up until I came here like promotions, managment, and proshop, and my micromanagment powers that be, I would have had no time, had I wanted to)

On the other note.... I swear by 'd'bores, and absolutly hate the super clutches. (never had a 'd'bore ut into the shaft, but might be also due to the slower lifts)

[Alastair]

Re: To grease or not to grease, that is the question...

We run slower lifts also. 5 inch pulleys. It didn't take long for the damage to the shaft occur, it was just by fluke that it had to come out just after the bearings were replaced. (clutch i think)

[TheGMan143]

Re: To grease or not to grease, that is the question...

Most bearings today are of the "sealed" type, that is, with closed sealing rings that are pressed and lapped so you would have to destroy the seals or damage the lip of the races to remove them. This type of bearing is prelubricated with sufficient grease of the correct type to lubricate it over it's usable/expected lifetime at it's designed load and speed.

"Repackable" bearings have seals that can be deliberately removed to service the bearing (without damage to the bearing), and then replaced to reseal the bearing race and it's grease from contamination. While they may look like sealed bearings, there is usually some type of groove, retainer, or other manufacturer-documented method to remove the dirt seals without damage to the bearing... the seals may be re-usable, or might have to be replaced with each rebuild... it depends on the manufacturer and the type of bearing.

"Open" bearings are usually seen only on the interior of a closed gearcase or cover that acts as the "seal" that prevents lubricant contamination by dust, dirt, or moisture, or bearings that run in a lubricant bath (as inside an oil-filled gearcase). Other open bearings would be the kind on your universal joints in your car... open pin bearings inside a cup that is open on one end. In this case it's the rubber seal on the base of the shaft it's applied to that provides the seal.

Truly "sealed" bearings do not require cleaning/repacking before use, in fact, trying to do so usually voids the warranty on the bearing. Repackables and open bearings need to be cleaned and repacked before use, and then redone at regular intervals to keep them lubricated properly and to prevent premature failure from wear, unless they are running inside an assembly, where the oil/grease bath surrounding them provides the necessary lubrication. As long as the assembly is serviced and the lubricant changed as suggested, the bearing as a unit does not require separate repacking or servicing.

[Coors]

Re: To grease or not to grease, that is the question...

i steer clear of the unrepackable bearings. i repack mine at least every other year, and repack motor bearings every 3-5years. i have a lithium based Blue colored grease i like. i religiously keep bearings lubricated when not repacking with a spray on Teflon Lubricant. Basically The Teflon Aeresol has taken the place of 10W-30 with me.

i too like D-Bores as Dorsin does. never had a prob. certainly had problems with straight bores turning into lathes.