Farmall Cub

I have been having a constant issue with my PTO properly engaging when trying to mow with my Woods 42c Mower. I did move the lever guide back a bit and that seemed to help for a while but was trying to mow a few weeks ago and couldn't even go 5 feet without the PTO popping out.

I finally had the time to work on it this weekend and messed around with the lever guide again but finally just pulled it back in the garage and pulled it all apart. The pin on the internal PTO lever was worn off again, I had redone this last year hoping this may help but not so much.

From doing some searching thought the forums last night it appears my PTO shaft is too far apart from the main shaft. I didn't actually measure it but I am guessing it is a good 1/4 inch apart if not more.

Any advice where to start? I have a bad feeling this is going to call for a split.

I apologize if this is a repeated question, but my time to search the forums and work on the Cub is pretty limited with 3 kids in sports and working 11+ hours a day.....

I took this pic inside the tranny fill plug with the collar off the shaft.

Thanks for the help guys!

to start with, the ends of the splines on the transmission shaft are worn off from the shifter apparently not engaging fully, which is going to keep causing a problem till it is replaced or taken to a machine shop that can fix it. I do not know what kind of repair you did on the shifter pin, but it is a hardened steel, and a bolt, etc. welded in place will not last. There is a good possibility that the pto pilot bushing also needs replaced, which will also cause wear problems.

the shafts should almost be touching when in proper placing. In the picture it shows them way too far apart. Causes could be pto shaft improperly installed on PTO bearing. or the driveshaft for some reason has moved forward. The replacement shifters do not have a hardened pin like the originals. The worn out pin can be drilled out then replaced with another that is of grade 8 or higher.

You may want to check the retainer on the front of the transmission. If it is in backwards then the shaft can move toward the clutch, and it will allow the two shafts to move apart. Look at the pic below #30 is the retainer that I am talking about.

Sorry for the dumb question, but I assume the only way to be sure this retainer is on correct is to split at the rear?

you can take the shifter top off the transmission to expose the shaft. you can get vicegrips on the shaft then with a pry bar you can see if the shaft moves forward or aft. should not move either direction..

I have the exact same problem with my cub! The shaft coming from the tranny is too far away from the PTO shaft.

You can add me to the list of people with that same problem. I think gap puts too much pressure on the end of the splines. Then they wear and round off. Once rounded off like that then they are always trying to screw themselves out of the coupler when under load. The only thing holding the coupler engaged is the pin on the shifter lever. This puts too much pressure on the pin on the shifter and wears it off in short order. So the worn off pin seems like the problem when in actuality it is a symptom of the problem.
I figured instead of splitting the tractor and moving the shaft back I would try to extend the splines on the coupler out to get a hold of them. I built my coupler out with a bead of weld then faced it off in the lathe . Then I filed the splines into what i had built up. It Got me through this year at least and didn't cost any money. We will see how it holds up.

gusbratz wrote:I built my coupler out with a bead of weld then faced it off in the lathe . Then I filed the splines into what i had built up. It Got me through this year at least and didn't cost any money. We will see how it holds up.

That is some nice machine work. I would add that your assessment on the shift pin is spot on. Once the shaft or collar loses it's square on the end, the rotational torque starts trying to pushing the collar off the shaft rather than concentrating all of the torque on rotating the PTO. The shifting pin was never designed to withstand this lateral pressure. It's function is only to slide and properly position the collar over the two shafts. If the collar is not properly centered over the two shafts, or the shafts are too far apart when the collar is in the drive position, the life of the entire shifter mechanism will be shortened. I will add the obvious caveat that you should always wait for the drive shaft to stop spinning before trying to engage the shift collar.

It looks maybe mine might have the same problem. The last pto shifter I put in I had to tie it back with a bungee to make it stay in gear. When I took it out it had sheared the little tip off that moves it in and out. I talked to 2 people at CUBARAMA and they both agreed that probably by transmission shaft is ground off which means a split of the tractor. I sure hope not as I don't think I have enough knowledge to put it back together.

now there can't be that many with the retainer installed backwards unless they were doing it wrong at the factory. so what makes that shaft shift forward like that?

gusbratz wrote:now there can't be that many with the retainer installed backwards unless they were doing it wrong at the factory. so what makes that shaft shift forward like that?

The normal cause for the retainer to be installed backwards is someone removing and reinstalling the shaft, either due to a bad shaft or bearing, or someone removing the retainer to replace the oil seal or gasket and putting it in backwards. The way it looks correct is actually backward. The space in the picture can also be caused by the pto slipping out a little in the pto bearing. Later bearings were held in place with a snap ring in a grove,but earlier ones were staked to the shaft and are known for moving.

Well I was finally able to get back out to look at this last night. I did not feel any movement in the main shaft so it seems like my retainer may be in backwards. I did inspect the PTO shaft assembly a bit more and there sure is quite a bit of movement in the shaft/bearing. I did not feel any back and forth movement but I bet the PTO shaft has about 3/4 inch movement side to side. Of course all of this is with the whole PTO assembly out and on my workbench. This cub is a 48 and it seems to have been used pretty hard so I am guessing at some point over its 65 years of life the main shaft may have been removed for one thing or another and the retainer was put back on backwards.

Seems to me I have a combination of issues with a possible backwards retainer and a wore out PTO assembly.

Thoughts?

Update: Well I took the mower deck off last night, drained the gas and wedged the front to prepare for the split to get to the bottom of this PTO issue. Before I start with taking the hood and whatnot apart I wanted to see if there was any members who have delt with this reversed retainer issue before and if there are any tips out there? I am really hoping to get all this taken care of over the weekend.

Since I am dealing with the main shaft do I need to split at both the middle and rear, or just the rear and no need to disassemble hood and whatnot?

Any help from the pro's would be greatly appreciated!

Thanks guys

before you split it, make sure the shaft will move forward and reverse. It will be hard to move, not slide easily. It will need to be split at the front of the transmission, leaving torque tube on engine. I believe if you check the HOW TO section there are tips for it. Not necessary to remove tank, everything from the front edge of the transmission will move forward as one piece. Do not forget to wedge the front axle.