Transmission input shaft bearing

[bob in CT]

I also recall George posting about this on the ATIS forum. But my recollection is that the grinding of the shaft to accept a sealed bearing is for the earlier Cubs. Bob has one of the newer Cubs. Is this procedure applicable to both?

The bearing George mentioned is a 1.65 OD for the early Cubs (up to the break in '54).

The needle bearing Cubs have a 1.126" OD bearing or about 32 mm.

Bob

[BigBill]

The bearing manufacturers really do have the lubrication of sealed bearings figured out. Why on earth would anyone screw them up by removing the seal?

The problem with the original bearing was two-fold... the rollers running directly on a shaft that isn't especially hard (a worn out bearing means a worn out shaft) and a lubrication system that stinks (crud in the galleys or feed hole means failure, as does improper assembly). If IH had spent a few more cents and used a sealed bearing in the first place it would still be good. Notwithstanding, many Cubs have lived for more than 7 times their design life using the original faulty setup, but that's no excuse.

Wait were running harden rollers directly on the shaft? There's no inner harden sleeve for the rollers to ride on.

We opened up the sealed bearings to see how much grease was in them when they were brand new. I had a bushel of failed ball bearings that we would change out often on the motorcycles. I ended up taking the plastic seal off and filling them with a tad more grease so they would last a little longer. Another fix was to put a zerk fitting in the center of the hub and remove one plastic seal on the inner side so the outer side stayed sealed. Then we would pump up the hub with water proof grease. After each outing/race we would give the zerk a shot of grease making sure it stayed lubed.

If the bearing is submerged in gear oil why not remove the seals? Let the gear oil lube it. If there is a problem with oil getting to the bearing than we should looks at raising the level of the oil in the tranny/diff a little higher so there is more lube in it. It shouldn't be no biggie to do. On my int154 with the hytran in the tranny(hydraulic tank) the rear cover has the oil fill plug higher anyway. Maybe we need a higher check plug on the side of the tranny to solve the starving problem of this bearing.

Do we need to make an engineering change this late in the game on this tractor too? We can add a half moon type washer to the side of the bearing to capture some oil as in a bath tub design to keep oil in that pocket halfway up the bearing from the bottom if there is room for one. It can be pop riveted in place or bolted. Is there room on both sides for this option?

My sons race bike we had a problem with the tranny with one needle bearing. It would burn up in a short time and we couldn't understand why only his bike was doing it. I found out when we split the case they had a hardened thrust washer infront of the bearing that blocked the gear oil from getting to the needle bearing. I had to groove the case to feed the bearing gear oil. I contacted the Kawasaki engineering group and told them about it. I built the engine and it had more HP so that one bearing that was already on the edge of failure showed up quicker. While they used the correct bearing design for the load its the lack of lube that was the problem. The needle bearing took a higher load over a ball bearing there's more contact area.

I need to take my extra tranny apart and check this out closer. There has to be a fix so it can last longer. I'm not fixing this over and over again.

I just ordered my moly today for the tranny and the engine but i will probably raise the oil level too when i clean/restore my tranny.

[Donny M]

Bill,
As others have stated, the bearing in question is near the top of the tranny case well out of the fluid, if the level is correct. This bearing relies only on splash from the gears on the pinion shaft. There's a galley cast into the case that provides a path to the weep hole directly above the bearing.

[bob in CT]

Bill,

I'll be able to show you on mine if I can get out there. The entire upper shaft and reverse idler could get better lubrication, but like George said, the longevity is nothing we can complain about!

I have a funeral to attend tomorrow, so my plans for Saturday have changed. Just got the last 2 shims (.003) so I can try to set the backlash up now. I don't know where this week slipped away to....

Bob

[Buzzard Wing]

I would think a sealed bearing would last forever in a Cub.

By the way, I had a battle with Kaman over some bearings I ordered for a snowmobile. I was really specific about the part number and MFG. It had a non contact rubber seal on one side and something else on the other. What they sent me had aluminum shields.... worst part was it was all that I needed to put the machine together. I would have a hard time ever dealing with them again, but they did get em air freighted to me the next day (free). I wish I had noticed earlier that the two original (alu shields) bearings they sent me were the same as a PTO in a Cub.

The moral of that story is that a 6905 bearing is NOT just a 6905 bearing. The dimensions may be the same, but seals, shields and all kinds of things beyond the dimensions (fit) make a difference. Something that goes from -20 F (considerably warmer the night before) to however many RPMs that equals 45 mph in a few minutes requires the best bearing technology available. I would not put the same bearing in a PTO that I would put in a chain case of a snowmobile because the use, abuse, temp, lubrication, etc is so much different. But I will not skimp on the PTO bearing.

The reason you see trailers with blown bearings on the highway is mostly due to cheap bearings and seals in the hubs.... Nobody is willing to pay more for a trailer with good (USA/Can/Japan) bearings till they fail. Too late!

I won't rant about the axle bearings I got from NAPA...

One thing to remember is that the bearing technology during WWII when the Cub was designed is very different from today. But I don't think you could buy a 'bad' (cheap and destined to fail) bearing back then either. I would be willing to bet very few bearings replaced in a Cub are due to wear or even lubrication, more likely due to water/rust and contamination. I just repacked the front wheel bearings in my 49 and they were fine. Never seen a tapered roller bearing without a cage before, I suspect they were original.

[Buzzard Wing]

Found some interesting reading about bearings on the NTN website.

This big PDF (1.8M) is worth reading or looking at:
http://www.ntnamerica.com/pdf/Other/9102cat.pdf


The main page is
http://www.ntnamerica.com/catalogs.htm

[BigBill]

I did notice one thing when i was looking over my cub for the first time. The side oil level hole seemed really low. I worked on all sizes of standard tranny's from cars to HD 4x4 trucks and never seen a check oil hole that low in the tranny? It thru up a flag in my mind right away but then i said if IH designed it that way it must be right(?) there the pro's.

I really think the oil level being too low is an engineering oversite that we can correct by adding more oil. Lets face it the oil is at the rear of the differential case while the tractor is moving so that upper bearing in the front gets starved of oil. Now that i understand the problem GW is right by trying to fix the starvation with a sealed bearing in that position.

I have seen shields on bearings made out of sheetmetal added to the housing to make a oil bath tub so the bearing gets the splash from it and what ever splash is in the area that it can capture. Its just a little half moon washer that they add. I have also seen this sort of sheetmetal guard in the japanese tranny's on the early motorcycles too they make the oil go were its needed by guiding it.

When I help Bob in Ct with his tranny i'll get a closer look to see what changes I can make to better the bearing life with more lube.

Trust me I know about the engineers and what they do and sometimes its not always right for the application. Bearings need a lot of lube so they run cool too. The Oil is cooling and lubing at the sametime. Like on my sons new dirtbike the bearing gets destroyed so fast, the heat and lack of lube is a killer.

We need to get Billie & Millie in on this too with the PTO dyne. I have a great test for you on the dyne. Lets do a run for heat on the dyne with just 90wt gear oil alone. Take the temps as it gets hot to see were it max's out. Then add moly of course when the tranny is stone cold the next morning then repeat the heat test to see how much lower the temps will be. Lets put the moly gear oil to the test. If your interested in doing it i'll send you the moly additive, but we need to use the same gear oil in both tests too. Let me know if your interested so we can see the results and have some concrete facts.

B&M; If you could do three heat tests;

1. 90wt gear oil filled to the proper level
2. 90wt gear oil filled above the plug hole(more oil)
3. 90wt gear oil with moly added, oil filled above the plug hole(more oil)
You can use the same oil for all the tests. The first sign is that were lowering the heat thats a big plus in bearing /gear life too. If the oil runs cooler it has a high viscous thus less wear.

Don't forget Wear is our enemy.......


Now with bearing numbers ther eare many different types of bearings with the same number. Some are shielded while some have seals and others are open both sides. Its the prefix after the number that says what the bearing is. I ran into this with the starter/generator ball bearings. Luckily I found the right ones on Ebay that were like $1 each.

We must beaware that the same bearing number can have the same OD and have different ID's(shaft sizes) with the same number but the part number will be different yet it has the same bearing number why is this i don't have a clue.

You need to measure the OD, the ID and the width of the bearing before going shopping using just the number isn't good enough, trust no one, the check isn't in the mail on this one. I been there too...

[BigBill]

Bill,
As others have stated, the bearing in question is near the top of the tranny case well out of the fluid, if the level is correct. This bearing relies only on splash from the gears on the pinion shaft. There's a galley cast into the case that provides a path to the weep hole directly above the bearing.

Thanks Donny for pointing that out. I remember seeing the weep hole when i pulled off the shifter housing to take a peek in my tranny to see what the noise was all about. But were that drip hole is there isn't much oil there too with the level being too low and the forward motion of the tractor sending all the oil towards the rear in the housing. The bearing is getting a double wammy. I truely believe right now in raising the oil level in the tranny will help this problem out.

[George Willer]

Bill,
As others have stated, the bearing in question is near the top of the tranny case well out of the fluid, if the level is correct. This bearing relies only on splash from the gears on the pinion shaft. There's a galley cast into the case that provides a path to the weep hole directly above the bearing.

Thanks Donny for pointing that out. I remember seeing the weep hole when i pulled off the shifter housing to take a peek in my tranny to see what the noise was all about. But were that drip hole is there isn't much oil there too with the level being too low and the forward motion of the tractor sending all the oil towards the rear in the housing. The bearing is getting a double wammy. I truely believe right now in raising the oil level in the tranny will help this problem out.

Bill,

Be careful! There may be some here who are as inexperienced as you are and may be missled by your unfounded ramblings. One thing that comes up often is the problems caused by overfilled transmissions. Your beliefs have no place here unless they can be backed up by known and demonstrated facts.

Here's the fact: The bearing in question has slowly failed after nearly 60 years in service in some cases and over the same time spoiled the input shaft. The modification to use the sealed bearing is intended to make it possible to use the expensive shaft again after slight modification.

Another fact: The variation in the bearing number to indicate the proper seal is the suffix. All bearings in a given series have the same O.D., I.D., and width. Study up!

[BIGHOSS]

Went to local NAPA today and got a sealed bearing. It was too pricey, but got it anyway as I already have the machine shop set up to fit it to shaft. The price is $29.89 and NAPA p/n is 6004-2RSJ. It is a sealed one with 42mm OD, 20mm ID and 12mm width. I assume that the fit to the shaft should be a snug (technical term) one.

We need to find a better source for this bearing. There are tons of 6004s out on the web for a much better price, but can't be sure if it is this same bearing. I want to touch and feel the bearing to make sure it is what I want. I can't do this via computer. As G. Willer said the suffix is important to identify the correct one.

[Boss Hog]

I think IH has the oil level where it needs to be. The problem more than not was contaminated oil or no oil because of leaks. The cub has servived for 60 years. Adding more oil will cause a lot of problems I can assure you of that.
I have pulled down transmissions that I no have not been torn into before me that the bearings were in usable condition, and have many many hours on them. More oil is not the answer.
My 2 cents worth
David

[Jack Donovan]

If there is a failure to a bearing it is more than not likely that the oil is dirty and old. Lube holes pluged, and the list gos on. If you dont think there is enough oil getting I suggest you pull your shifter off and put it in gear and drive down the drive and back. If you don't get a oil bath you had no oil in it to start with. It lubes fine if all galleries are clear

[Gary Dotson]

For some reason, NAPA is crazy high on small bearings. I too have been caught in a pinch and had to buy from them. I generally order bearing on line from McMaster Carr. They have a good bearing section, in the catalog, with excellent specs, making it easy to choose the correct one. The price is very good and the order will be on your door step the next day.

Bill, the dyno won't show anything on an oil test. When running the PTO in stationary mode, the only friction is from 3 bearings, none of the lower gears are turning.

[George Willer]

For some reason, NAPA is crazy high on small bearings. I too have been caught in a pinch and had to buy from them. I generally order bearing on line from McMaster Carr. They have a good bearing section, in the catalog, with excellent specs, making it easy to choose the correct one. The price is very good and the order will be on your door step the next day.

Bill, the dyno won't show anything on an oil test. When running the PTO in stationary mode, the only friction is from 3 bearings, none of the lower gears are turning.

BTW... the idea of using the sealed bearing for replacement of the roller bearing wasn't mine, it was Gary's. He should receive full credit.

[Don McCombs]

I believe, the McMaster-Carr part number for the bearing being discussed is 2349K191.