Cub pto

[stanleygibson]

Hey y'all.
Seeking wisdom from the group
When I try to engage the pto that is to slide the splined hub forward from the pto shaft to the transmission shaft it doesn't engage firmly and jumps out. Visual observations into the assembly shows the distance between the two shafts is greater than on other working cubs. Someone suggested a bearing has been installed wrong. Either not seated or installed backwards. Any suggestions on how to determine which bearing is wrong. I see one is:
Transmission spline shaft 351 534 R21 with the bearing:
Front Bearing transmission spline shaft ST 542
I think that requires splitting the tractor?
The other is:
PTO shaft 368 433 R91
PTO take off shaft bearing ST 225B
That one is easy to remove

[Glen]

Hi,
If the Cub has too much space between the rear end of the long clutch shaft, and the front end of the PTO shaft, it may be the bearing retainer and oil seal has been installed backwards. That is at the front of the transmission.
Installing it backwards lets the clutch shaft slide ahead, by about 1/4". Then the PTO clutch won't have much splines to hold on to, at the rear end of the clutch shaft.
I don't think there is any bearing that being installed backwards would affect it any.
Yes, you have to split the Cub at the front of the trans to get to the retainer.
You didn't say the year of the Cub.
Below is a pic from TM Tractor Parts of the retainer. One side of it is flat, and one side has a bulge.
The bulged side has to face to the rear, or into the transmission, to hold the ball bearing on the clutch shaft to the rear.
The front ball bearing, which is just to the rear of the retainer, should be tight on the clutch shaft, to hold the shaft in one position.
Below is a listing at TM Tractor Parts for a new retainer, you can look at the pics.
http://www.tmtractor.com/new/tr/431fp.htm

The 2nd pic shows the shaft and retainer at the front of the trans.
If the retainer is backwards, the oil seal probably won't seal well, it is made to face one way.

The other possibility is the PTO shaft has slid to the rear. It should stick out of the housing a certain amount. You could try using a hammer to hit the end of the PTO shaft and see if it goes ahead, if needed. I would put a small wood block at the end of the shaft to hit on, so you don't damage the splines.
Below is a page from the 1965 Cub operator's manual, with specs for the PTO shaft, at the bottom of the page. You can measure how far it sticks out of the housing.
https://farmallcub.com/rudi_cub/www.cle ... age-73.jpg

[stanleygibson]

52 Cub. Thanks for the insight Glen. I'll look closer at the PTO shaft position and then if needed try to get courage up and split it.

[Dale Finch]

For a real quick and dirty check, grab the PTO shaft where it sticks out the rear of the tractor, and try and push and pull to see if it moves any. It should not. It takes very little movement of that bearing in the seal retainer right there, to cause the shaft to move rearward and increase the gap between the PTO shaft and the clutch shaft.

Not saying that this is the problem, but it's a pretty easy way to investigate one possible source.

Also take a quick peek through the transmission fill plug at the shifter pin, to ensure that it is still round and does not have worn flat edges to it. Should be a nice cylindrical shape. If it is worn flat, that is also a fairly easy fix... Not requiring any tractor split.

[Glen]

Dale mentioned another possibility, the pin on the PTO Lever and Shaft could be worn.
Below is a listing for it at TM Tractor Parts, you can look at the pics. The pin that runs in the PTO clutch groove is at the bottom of each pic.
Use a light to look in the transmission oil filler plug hole, you can probably see the pin in the groove.
The pin should be round.
To show where the part is, the PTO lever that you shift with your hand goes in the hole in the large part of the shaft.
You have to remove the PTO, out the rear of the trans housing, to replace the PTO Lever and Shaft.
http://www.tmtractor.com/new/pt/317fp.htm

[dgrapes59]

If the lever shaft is worn, Hamilton Bob's also offers the part, with the lever. Don't know how the quality compares, but the price is about half.

https://hamiltonbobs.com/cart/351287R11 ... =pto%20lev

Good luck,

[Dale Finch]

If the lever shaft is worn, Hamilton Bob's also offers the part, with the lever. Don't know how the quality compares, but the price is about half.

https://hamiltonbobs.com/cart/351287R11 ... =pto%20lev

Good luck,

That IS a good price...thanks!

[Bob McCarty]

If a worn pin is the problem, you can also repair them by removing the worn pin and silver soldering a piece of drill shank into the hole.

[Eugene]

If a worn pin is the problem, you can also repair them by removing the worn pin and silver soldering a piece of drill shank into the hole.

If the pin on the shift lever is worn, the splines in the clutch are probably worn. Replace the shift lever and clutch.

[CharlieK]

^^^^^^^^^^^^^^^^^AGREE