PTO trouble on '53

[k hutchins]

Ok guys, I finally found the time to work on the friend's cub pto. Once I got it apart, what I discovered was that the pin that moves and holds the collar in place is worn 3/4 of the way through, therefore there isn't enough of it there on the front side to push the collar forward enough to engage the drive shaft.

Now for the question.
I see that the parts are available, but I'm not sure how it all goes together, is there a pin at the bottom of the shift rod? Or am I missing something?

By the way, the reason it's worn down is because someone removed the shift lever guide, and probably just jambed something against the shift lever to hold it in place while operating the pto, therefore keeping constant forward pressure on the pin in the collar.
Before anybody suggests it, I plan on replacing the collar too. I'm assuming it is worn down too if it took that much off the pin.

Thanks in advance for the help.
Hutch

[Bob McCarty]

You can buy a new one or repair the old one by drilling out the pin and welding/silver soldering a piece of hardened rod back in (cutting off the shank of a drill bit works fine).
I would doubt that you need to replace the clutch (I think that's what you are calling the collar).

Bob

[k hutchins]

Thanks Bob
After getting the old one out, it's cheaper and easier for me to replace rather than try to rebuild. I have to get a new guide anyway so just ordered a new shifter.
After cleaning up the shaft and collar, it appears that the shifter was "sacrificial" as the collar didn't appear to be excessively warn at all. So I will hold off replacing it until I get it back together and see if I still have a problem.
Just waiting on parts now.
I'll let ya know how it all comes out.

[Glen]

Hi,
The Cub parts book says there is a 1/16 x 7/16 cotter key in the bottom of the PTO shifter lever. Take that out and the lever comes apart.
Here is a pic of the front of a new PTO clutch from TM Tractor, this is how a new spline looks. If the splines are worn much on the clutch you have, it would be good to replace the PTO clutch.
The PTO pilot bushing in the end of the long clutch shaft needs to be good too, if it is worn, it should be replaced. The front end of the PTO shaft should be smooth, it runs in the bushing.

Here is the listing at TM Tractor for the PTO shifter guide, it has a pic of how the lever and spring fit together, below the pics of the guide.

http://www.tmtractor.com/new/pt/245fp.htm

[k hutchins]

Well, I thought I had it handled. Installed the new shifter, put everything back together (correctly) finished a few other odds and ends, then took it for a test.
The pto engaged but then started grinding, and was not spinning. Now we're back to won't engage and just grinds when the shift rod is in the engaged position. Obviously it isn't going far enough forward to catch the splines on the shaft, or the splines on the inside of the collar are stripped. I plan on ordering a new clutch/collar unless someone has a better idea. If it's the splines on the shaft, I'm done. This is a project for a friend and I'm not a good enough mechanic, nor am I getting that involved in it to replace the shaft.

Now for the next problem.
I believe I either have a govenor problem or a carb problem or both.
When I was just driving it there was no problem, when I initially put it under load with the pto it wanted to stall.
After it did stall, I disengaged the pto, started it, it would idle then as the govenor arm moved to cal for more fuel it would stall again. Did that several times. Finally got it to run long enough to get it back in the garage, ran the throttle up while in first gear and it was fine, the govenor picked up like it should, but still touchy and rough.
I would appreciate your thoughts on this problem as well. Beginning to think I bit off more than I wanted to chew.
This tractor sat for 4 yrs without running. I didn't do a tune up as all it needed was fresh oil and gas and fired right up.
As always, thanks in advance for any help.
Hutch

[Glen]

Hi,
The PTO guide needs to be adjusted so the PTO lever goes to the rear as much as it will, the guide will turn some on the bolt holding it on. Loosen the bolt some, and engage the PTO, and twist the guide on the bolt so it is to the rear as much as it will, then tighten the bolt, if the lever binds, move the guide ahead slightly until the lever doesn't bind.
Sometimes the clutch shaft and PTO clutch have to be replaced to get the PTO to work right.
A man posted several months ago that he couldn't get his PTO to work right until he replaced all the parts.
The parts wear out after being used for years.
Sometimes the front transmission seal retainer has been installed backwards, then the long clutch shaft can move ahead, making too much of a gap between the clutch shaft and PTO shaft. There was a post about that a few days ago. The tractor has to be split to fix that.

If the engine is cold or not fully warmed up, it needs the choke on some, it might stall when you put a big load on it.
If the engine was warmed up enough that it didn't need the choke on some,
the stalling could be a fuel flow problem, or the carburetor dirty and needs cleaning.
Remove the carb drain plug, and catch the gas in a clean can. Be sure the fuel valve under the gas tank is fully open. There should be a steady stream, let it run out for 30 seconds to 1 minute.
If the flow is slow, the strainer under the gas tank could need cleaning, it has a screen in the top, above the glass bowl, it could be plugged some. It could also have dirt or something in the gas tank blocking the inlet into the fuel strainer.
Or the screen at the inlet in the carb could be plugged some. It is where the pipe screws in the carb.
TM Tractor has new screens, and the strainer bowl gasket.
The vent holes in the gas cap have to be open too, they can get plugged with dirt.

[k hutchins]

Thanks Glen
I didn't want to get into the carb if I didn't have to. The bowl, upper screen, and gasket were replaced initially. My 48 doesn't have a screen in the carb at the line connection, so I'll start there.
As far as the pto goes, I believe the splines on the inside of the clutch are worn due to previous abuse. The splines on the drive appeared good, and the gapping was good between the two (dbl chkd that when I reassembled having read previous threads on pto). Someone had removed the shifter guide and then jambed the shifter back to hold it in gear causing the shifter pin to wear down to almost nothing. That's where I started.
Thanks again, now to dig back in.

[Glen]

Hi,
You are fortunate if the clutch shaft spline is still good.
When taking the carburetor apart, pull the 2 halves straight apart, do not twist them, you can break the small idle tube.
Be sure to take out the main jet and clean it. Could be partly why it doesn't run right.
Here are 2 pages from the Cub parts book showing the IH carburetor. The pic is helpful to see how it should fit together.
I would soak especially the top and bottom castings in solvent, or carb cleaner, and then blow all the passages out with compressed air. Dirt settles in the bottom half, but could be anywhere inside the carb. Wear your safety glasses when using the air.
The float level needs setting accurately. If it too high, the carb can drip on the ground when sitting, or not run right. The needle and seat can be wornout too, and not seal, then when the Cub is sitting, it will drip on the ground also.
When you get it put together, the idle screw on top of it should be open 1 - 1 1/2 turns, the owner's manual tells how to adjust it, you run the engine at idle speed, supposed to be 500 RPM, and listen to the engine, while adjusting the screw. Set it so it idles as good as it will.
It says adjust it when the engine has warmed up.
The idle tube is number 10 in the pic, and the main jet is number 28. They screw into the castings.
The 3rd link is a page from the Cub service manual showing the IH carb in the top pics, the float level is measured without the gasket between the halves there. Good luck.

http://www.farmallcub.info/manuals/cub_ ... 012-12.jpg

http://www.farmallcub.info/manuals/cub_ ... 012-13.jpg

http://www.farmallcub.info/manuals/gss- ... 002-09.jpg

[Cubfriend]

Was just over at a friend of mines last night and discovered his PTO problem was the main transmission shaft retainer was installed backwards and the main shaft moved forward to disengage the PTO. Thanks to this forum for all of the information it provides to us novice Cub owners. It's a real time saver.

[k hutchins]

Thanks again Glen, carb is 2nd problem to tackle.
I just ordered a new pto clutch collar. Will get that back together first.
in one of the threads I read about the space/gap between the drive shaft and the pto shaft. But I can't find it quickly. I have no doubt the driveshaft hasn't been changed so there should be no problem there.
However what should the gap be? After removing the clutch I put the pto shaft back in, and it appears that there is about a 1/2" gap.
the other problem is that the splines on the driveshaft appear to be worn down/rounded off on the very end (damn). I'm hoping that a new clutch will have enough bite to grab the driveshaft splines.

[k hutchins]

Somewhere when chkg old threads I thought I saw what the gap should be between the trans/clutch spline and the pto spline. As luck would have it, I can't find it.
In reading from the manual (6a) it gives a cpl dementions, I believe it is in the neighborhood of 3/8".
Could someone verify this for me please?

[Glen]

Hi,
Keep doing a search on this site, I think they have discussed what the gap should be before.
If you have a 1/2 inch gap, it sounds like the front seal retainer is backwards. Maybe it was worked on before you bought the Cub.
If you have the PTO out of it, see if you can pull the long shaft back, towards the rear, with the transmission in neutral. If it moves 1/4 inch or so, probably the seal retainer is the problem. My opinion.

[k hutchins]

Thanks again Glen, I hope it's not the shaft seal. Doing this work for a friend and didn't plan on having to go that deep. I'll chk it for travel as you suggest. Wish I could relocate that thread.
I also received the new clutch collar today and when comparing it to the old on it appears that the interior splines are a full 1/8" closer to the end than the old one. Hopefully that is enough to engage and fix the problem, along with adjusting the lever guide back as suggested.
Haven't pulled the carb yet. That's next after I get the pto prob solved.
Thanks again.

[k hutchins]

Hello all
Well I got her done. She is back home with her owner.

PTO needed a new shifting lever as the old one had the pin worn down to nothing, and a new clutch collar. I also replaced the guide plate and adjusted it back per Glen's recommendation. It now works perfectly.

As far as any running issues, fresh gas and oil/with new filter, took apart and cleaned carb (didn't really need it, but as long as it was off), new plugs, and a new coil wire (just because I had one).
Runs like a champ. I had to drive it back to the owners, about 2 miles, and the longer it ran the smoother everything seemed to get.

Thanks again to everyone who had input, I do appreciate it.

Next project, I know where there is a '73 that needs a new bolster. If I can get it for the right price? ;-)