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Discussion Starter · #1 ·
On 740 with about 1000 separator hours shaft was wearing at bearing on RH side of feederhouse header driveshaft (small 1000 pto splined shaft). The bearing is grease-able but is housed in greaseless flanges instead of a pillow block with a zerk. The LH bearing is the same bearing but claas decided to use a greaseable pillowblock there.

I am taking the shaft to a machine shop tomorrow to have them build up where the bearing was wearing through. A new shaft is $1200 and not in dealer network, would have to come from columbus. It looks like the RH side could be put back together with a pillow block same as the LH side so you could grease the bearings. Has anyone done that before?
 

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Definitely a sore spot in my books. That bearing was short lived in the 590’s as well. If there’s a way to make it greaseable do it!
 

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If the bearing is greaseable was there an assembly error and they missed putting on flanges with grease fittings? I don't know the size but most flangettes are available with zerks.
How will grease prevent the shaft from wearing inside the bearing? Lubrication may extend bearing life but does it help keep a bearing snug? Does the bearing have an extended inner hub? If not then try to fit one in. The wider hub will help to spread the load.
 

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All good comments. I have heard of people having issues with these bearings. I have about 3000 engine hours on a 2011 740. Neither side are greasable. Neither side has given me any issue.

I have heard that the people who have the most issues with these bearings run large, high load corn heads such as chopping. I personally would make sure the header driveshafts slide and are lubricated very well so it doesn't side load the bearing or maybe even push the shaft through the bearing.

INA has a good bearing website for finding and narrowing down bearing choices for different applications. I think they are also a good quality bearing, as are Nachi. Maybe consider a good shaft "loctite" when reinstalling, and use grub screws with a knurled cup.
 

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If the bearing is greaseable was there an assembly error and they missed putting on flanges with grease fittings? I don't know the size but most flangettes are available with zerks.
How will grease prevent the shaft from wearing inside the bearing? Lubrication may extend bearing life but does it help keep a bearing snug? Does the bearing have an extended inner hub? If not then try to fit one in. The wider hub will help to spread the load.
Is it that the bearing seized up and the bearing race started slipping on the shaft?
 

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Discussion Starter · #7 ·
Bearing was not seized up but must stalled out at times to cause wear on the shaft. Does not look like excessive heat or continuous stalling, probably momentary.

This is on a a machine with the 120kw variable speed drive so no gearbox on LH side. It is not an assembly error because old bearing is greaseable and new bearing is also greaseable. For whatever reason they put it in a greaseless flange? Will get a greaseable pillow block when I put it back together and see how it works. It has been used a fair deal on a 8 row chopping corn head driven from both sides but that is the most work the header drive gets. Outside of corn it's on a FD75 driven only from the left side.
 

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I've had the same problem on two machines now 580 and now 760. The RH bearing has no locking coller on it while the LH doesn't . The bearing turns on the shaft, a bad design problem IMO and no room to put a coller. Should of made the shaft 1/2 in longer to accommodate one. Let us know if you figure something out.
 

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Bearing was not seized up but must stalled out at times to cause wear on the shaft. Does not look like excessive heat or continuous stalling, probably momentary.

This is on a a machine with the 120kw variable speed drive so no gearbox on LH side. It is not an assembly error because old bearing is greaseable and new bearing is also greaseable. For whatever reason they put it in a greaseless flange? Will get a greaseable pillow block when I put it back together and see how it works. It has been used a fair deal on a 8 row chopping corn head driven from both sides but that is the most work the header drive gets. Outside of corn it's on a FD75 driven only from the left side.
The shaft is probably just made slip fit on the bearing instead of interference fit and once it starts to turn on the shaft it just keeps wearing.
If you have no room for a lock collar what you can do is have the shaft sized for .0005'' press fit.
But if it would be hard to put together with press fit on assembly just use loctite bearing and shaft retainer and no worries.
 

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Discussion Starter · #11 ·
I put a locking collar on the inside of the RH bearing. I did not use the pillow block on the RH side. I think it would be no problem to use the pillow block but it just makes the assembly and disassembly a little more complicated since you have to put the pillow block on before the bearing is on the shaft. Besides I think the bearing will last a long time as long as it is not turning on the shaft. Not sure why the engineers would do it like they did, seems to be a lot to depend on the friction against a little snap ring to keep the bearing from turning on the shaft. Especially considering temperature expansion/contraction, doesn't take much to provide enough gap to let the bearing start to slip on the shaft.
 

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Discussion Starter · #13 ·
Loctite between the shaft and bearing? I did not use loctite, just the lock collar. It is not put together yet I just tried the lock collar here at the end of the day.
 

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Well yeah in a situation where you seen a race work into a shaft there’s a good chance it’s under engineered and the lock tight will help considerably.
I’m pretty sure I seen that exact same issue on a 500 series actually. Which bugs the **** out of me because it didn’t get rectified on the 700’s. Same as the shoe drive shaft driven side bearing.
 
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