1850 rear axle bearing update

Got down to the axle and removed the end cap, bearing looks good, there was no noise and wheel turned smooth when it was still on. There were 6 shims on the end cap, so I'm planning to take 3 shims out and put it back together as soon as the new seal gets here. I was going to add a picture, but the stars are not aligned, so that won't work. The end cap has a flat place where a grease zerk could be added. I'm wondering about drilling and tapping a hole for a grease zerk. It would have to be drilled at a pretty good angle so the hole misses the grease seal. I think it would help the bearing to have some grease, but since it is lubed from the inside with oil, will the grease on the bearing cause an issue mixing with the oil and going thru the oil pump? Or just take the grease needle and give the rollers a couple shots of grease and put it back together?? Wish I could post a couple pictures, but there is no link to get to my pictures. Thanks, Chris

Why fart around with a grease zerk?
That axle bearing has apparently run for 50 odd years being lubed by the gear oil alone without the bearing giving out so me thinks it got plenty lube as is.

What thickness shims do you plan to remove?

Our 1850 has the end cap drilled and a grease zerk installed, it looks factory.

Rich

I agree with JS, apart from why are you removing shims? They are there to fix the end-float. The number and thickness of each are immaterial - it was the combined thickness that was varied, at build time, to give the correct clearance.

They may have used different shim thicknesses to limit the number required or they may just have fitted multiple shims of the same thickness, it being easier to stock that single size of shim or allow more incremental adjustment at later service/repairs.

(quoted from post at 18:24:50 11/12/18) Our 1850 has the end cap drilled and a grease zerk installed, it looks factory.

Rich

Click to expand...

Mine does too. I grease it about once a year. Not a ton, just about maybe 4 strokes.

Aside from bearing lube, my thought is that the grease keeps the seal lubed, and prevents seal failure.

Does yours have the zerks on the front wheel bearing cap too? Mine does, and I love it. Seldom does a guy pull a front wheel to repack bearings, and the zerk is an easy reminder, and easy to actually do the greasing. Forces any crud out too if you've run the machine in deep muddy situations.

I agree wholeheartedly.

All the specs I have, do NOT show endplay, only preload. Which in this case would be impossible to measure, given the tractor ain't in pieces. And preload isn't a good measure of correctness on old bearings, unless specs for old bearings are obtainable.

If they're turning, good, and freeplay is around .0015 (standard freeplay recommended by Timken for wheel bearing applications), I'd leave the shims alone. Don't fix what ain't broke.

To give you an idea what you're facing if you mess with the bearing shims.







I kind of like using feel when doing a preload, but this is what the Oliver boys recommend.

Edit: Where I say "freeplay", in the above post, I mean ENDPLAY. Paragraph 3.

Wish the editor worked, I still gotta coma where there shouldn't be a coma in the first reply.

Preload has always been a sore subject with me.

I do the occasional rear end, and have to set pinion preload. I've found that if you follow manufacturers specs, and methods, you'll generally wind up setting them too tight. A slight drag is a better indicator...…..but my slight drag probably ain't your slight drag :lol:

The trucking industry has had issues with wheel end bearings for decades. It's easy to set them up too tight, or too loose. It's why the cartridges are taking over. Gets real expensive when you lose a wheel at 65mph...…..it has lawsuit written all over it. The one, and one half, thou is a good compromise......heat expansion, etc......but try to get the doods to set them that way :roll:

I can't post a picture from my computer, only gallery photos show up, so I'll try to describe it as best as I can. Rear axle seal started leaking, the bearing went out on the other side a year ago, so I was figuring this one was done also. I put a dial indicator under the axle and jacked up the tractor till the wheel was off of the floor. Indicator said the axle moved 15 thousands. I repeated the same thing on the side we replaced last year and it moved 5 thousands. The wheel turned free with no noise or dragging. I got the wheel and hub off and removed the end cap, the bearing looks good from the end, so I decided to just replace the seal for now and take some shims out to tighten things up. I stopped and bought a dial caliper at Harbor Freight tonite and measured the shims. 3 shims are 1/64" .015625 and 3 are 1/128" .0078125. I put the end cap on with 3 1/128" shims and used the dial indicator again and the axle moved 8 thousands. So I figure that is better than it was and still not too tight. Hope this makes sense, Chris

I understand what you've done. You have measured axial runout to some degree. Bearings would have to be properly preloaded to get a real TIR (total indicated runout).

Without proper preload, it's hard to tell what's moving.

Could be bearing wear, or it could be shaft wear underneath the inner race on the bearing. Or it could be the entire assembly moving because the bearings aren't tight enough (think of the inner cone rollers moving against the outer race like a ramp)

A closer approximation, other than relying on feel to set preload, is to measure endplay.



If you can, by adding/removing shims, get to about .001 endplay, it's about as good as you can get. Once you hit 0, there's no telling. You can't measure negative endplay. It could be exactly touching, or it could be under pressure.

Install the mag base on something that won't move in relation to the shaft, and position the point point somewhere on the axle/hub. Push, and pull the shaft......then note total movement from "front to back". This is your endplay.

Once you're satisfied with endplay, then you can start to figure out whether runout is acceptable.

It's tough to feel preload, or use a scale/torque wrench to measure preload on an axle that's engaged with the differential. You always have the drag from the differential to consider. I run into this all the time on drive axle bearing replacement.

All this being said...…..Improper preload, especially preload that's just too tight by a little bit, won't always cause failure immediately, or sometimes even never cause failure. It simply accelerates wear on the bearing.

Quite frankly, I'm surprised that Oliver spec'd these at 12ft/lb preload at the outer axle shaft. That's mondo torque for a preload. Be interesting to have seen what it measured fresh off the assembly line. The manual doesn't say anything about seating the bearing before measuring torque for preload. Usually you tighten them up to seat them, then back off, and slowly tighten to determine preload.

Somewhat germane to the discussion, just to give you an idea what's involved with setting bearings in other enviroments which are somewhat relevant.

file:///C:/Users/sam/Documents/10410_Manual Wheel Bearing Adj Procedures Sell Sheet.pdf

https://www.timken.com/pdf/10410_Manual%20Wheel%20Bearing%20Adj%20Procedures%20Sell%20Sheet.pdf

https://www.timken.com/pdf/10410_Manual Wheel Bearing Adj Procedures Sell Sheet.pdf