Sickle bar mower, PTO, grinding noise

[Julien]

Hello,
The shaft was very firm in the housing. There was no play when I would try to pull on it. I have attached a picture, not sure if it shows what needs to be shown. If not, I can take another one with a close up of where the shaft meets the housing.

Is it possible that the bushing fell off into the transmission case when I removed the PTO? Otherwise, I guess it is worn off, and I need a new one.
I cleaned up the splines as best as I could to get a better look at the situation.

Looking inside the transmission... Not sure if the attached picture shows anything of value, but it was the best picture I could get.

Thanks for your help!
Julien

[Don McCombs]

I think your photos show evidence of the set screw in the collar being placed on the wrong spline and being tightened down to the point of not being able to move as designed. The last photo appears to show the bushing in place, but maybe not fully seated. Hard to tell with all the dirty gear oil.

[Gary Dotson]

I think the last photo shows the bushing missing, not too uncommon, just hope the bore of the isn’t too worn for a new bushing to fit. I’ve had to sometimes make a custom fit bushing, including the last 2 I’ve worked on. The alternative is to replace the clutch shaft. I agree with Don’s assessment of the pto shaft, someone has buggered it up, pretty good, somehow. If the collar fits and slides properly, it still may be usable, though. Lightly tap the pto shaft, first rearward, then forward and see if you get any movement. Movement would indicate a failure of the staking Dale referred to.

[Don McCombs]

Now that I look at that last photo more carefully, I agree with Gary. Looks like no bushing.

[Dale Finch]

Clean up the end of the main drive shaft (just wipe it off well), and take another photo like the last one, so we can see if there is any bushing left...it's too dirty to tell for sure.

There should be a yellowish ring visible in the center of the shaft:
http://www.tmtractor.com/new/pt/752fp.htm

[Glen]

Hi,
Thanks for the pics.
Before you disturb the PTO shaft's position in the housing it is in, I was hoping to see a pic of the rear of it where it sticks out of the housing, by the oil seal.
Then I can see if the shaft has moved rearward by itself, which they can do, if they are the staked shaft.
That can cause the problem of the PTO slipping out of engaged.

I can't see the area in your pic, it is dark. A pic with lots of light where the shaft meets the oil seal would be nice, like your pic here at the top of page 2, but with light where the shaft sticks out the rear.

[Julien]

Clean up the end of the main drive shaft (just wipe it off well), and take another photo like the last one, so we can see if there is any bushing left...it's too dirty to tell for sure.

Is the only way to clean off the main drive shaft by reaching my hand through the opening in the transmission case where the PTO housing was removed?

Lightly tap the pto shaft, first rearward, then forward and see if you get any movement. Movement would indicate a failure of the staking Dale referred to.

PTO shaft has been tapped. No movement detected.

In addition the the shaft splines being gnarled, is it possible I jeed a new set screw? It is also pretty beaten.

Thanks!
Julien

[Bob McCarty]

.
In addition the the shaft splines being gnarled, is it possible I jeed a new set screw? It is also pretty beaten. Julien

You should be able to get the set screw at a hardware store. If you end up buying a new clutch, it should come with it. If you haven't looked yet, TM Tractor has all the parts you might or will need.

[Glen]

Hi,
I posted my post above here again because we posted at almost the same time, and you might not have seen my post.

Thanks for the pics.
Before you disturb the PTO shaft's position in the housing it is in, I was hoping to see a pic of the rear of it where it sticks out of the housing, by the oil seal.
Then I can see if the shaft has moved rearward by itself, which they can do, if they are the staked shaft.
That can cause the problem of the PTO slipping out of engaged.

I can't see the area in your pic, it is dark. A pic with lots of light where the shaft meets the oil seal would be nice, like your pic here at the top of page 2, but with light where the shaft sticks out the rear.

Here is some new writing.
You can use a parts cleaning brush, with solvent, or a clean paint brush, with solvent to clean inside the housing.

Replace the set screw if it is damaged. The setscrew goes on the shaft where the spline is ground down in one area. Don't tighten the setscrew tight, so the PTO clutch can move freely on the shaft.
The set screw should be tight in it's threads, so it doesn't come out during use.

[Dale Finch]

You should be able to just reach into the differential with a rag and wipe the end of the shaft.

[Julien]

Thank you all for your help!

I was hoping to see a pic of the rear of it where it sticks out of the housing, by the oil seal.

I couldn't detect any bushing present when I looked in. Wiped off the area as best as I could.

And here's the set screw. Does it look ok to still use? If not, what size set screw am I looking for at a hardware store. Or, I guess it's probably just easier to bring in the old one and try to find a match?

I think I finally understand how this whole set up works. The set screw is just supposed to keep the PTO clutch engaged on the shaft to prevent it moving laterally, said PTO clutch is grabbed by the shifter pin and slides over the output clutch coming off the transmission. Hence why the set screw is supposed to be tightened just enough to keep the clutch in place while still allowing it to slide back and forth per the instructions in the maintenance manual?

As of now, I am going to order a new bushing and shifter shaft and pin. The PTO clutch when placed over the shaft splines seems to still lock in place pretty well despite damage to some splines. I'll try replacing the bushing and the shifter shaft and see if that does the trick.

And where do I find the right size cotter for the bottom of the PTO shift lever? The one I removed did not survive the removal.

Thanks!

[Glen]

Hi,
Thanks for the pics.
I was hoping to see a pic of the rear of the shaft, where it sticks out of the housing, by the oil seal.
That is between where the PTO pulley for the mower, and the housing is.
The oil seal is at the rear of the housing.
The pic you posted is where the shaft comes out the front of the housing.
I can't tell if the shaft moved seeing the front area of the shaft.

Glad you are understanding the PTO, it is sort of a simple design.

The setscrew looks different than IH used in the PTO. The originals have an allen head, for an allen wrench.

The Cub and LoBoy parts manual says the setscrew is 1/4" x 1/4" long, 20 threads.

I think the purpose of the setscrew is to keep the PTO clutch from falling off the shaft while installing or removing the PTO unit.
The setscrew CANNOT be tightened to the shaft. Tightening it fully would lock the PTO clutch, and it would not move.
The PTO clutch must slide freely on the shaft, the amount the setscrew lets it slide, in the cutout, flattened place on the PTO shaft.

The setscrew must be tight in the PTO clutch threads, so it doesn't come out during use.

If the setscrew is easy turning in the threads, it should be made so it turns sort of hard.
You could buy some thread locker product and put on the threads as you install the setscrew.
Permatex makes thread locker, I think it is a liquid.
Auto parts stores, NAPA, etc, probably have setscrews, cotter keys, and thread locker.

If you are using the same PTO clutch, I would take it to the store and then they can turn setscrews in the threads so you can buy the right one.
While it's apart is a good time to replace the PTO clutch, the one at TM Tractor says it comes with a new setscrew. Then it will have new splines on that part of the PTO.

Below is their listing for it, the 1st pic shows the setscrew, it has no head like the one in your pic.

http://www.tmtractor.com/new/pt/449fp.htm

The Cub parts manual says the cotter key for the PTO lever is 1/16" x 7/16" long.
Probably you will find 1/2" long cotter keys, which should be good enough.
Or they might have longer ones, then you will need to cut one to the right length.

I would take the PTO lever to the store, then they can try new cotter keys in it.

Below are pages from the Cub and LoBoy parts manual showing the PTO, and it's parts.

http://www.farmallcub.info/manuals/cub_ ... 007-14.jpg

http://www.farmallcub.info/manuals/cub_ ... 007-15.jpg

http://www.farmallcub.info/manuals/cub_ ... 007-16.jpg

Below is a pic from TM Tractor of the rear of the clutch shaft, with the PTO pilot bushing in it.
It looks like your shaft might be worn bigger than the OD of the bushing.
If it is worn, the new bushing would be loose in the hole.
One of the experts that posted said that he needed to make custom fitted bushings when the holes were worn.

[Dale Finch]

The Parts Manual shows the PTO clutch set screw size is 1/4-20x1/4", and should be available in a decent hardware store, or Fastenal lists them:

https://www.fastenal.com/products/details/1173257

I have used a very small dab of Permatex Thread Locker on the set screw. This is one type:

https://www.permatex.com/products/thread-compounds/threadlockers/permatex-high-strength-removable-orange-threadlocker-gel/

[Julien]

Greetings all,

I was hoping to see a pic of the rear of the shaft, where it sticks out of the housing, by the oil seal.

Roger that and thanks for the clarification:

It looks like your shaft might be worn bigger than the OD of the bushing.
If it is worn, the new bushing would be loose in the hole.

I ordered a new bushing, but rather than it being too loose, it wouldn't even fit into the hole in the end of the clutch. Perhaps the old bushing is worn down and embedded inside of the clutch?

As far as re-installing the PTO assembly, I had quite a time getting the shift lever shaft back through it's hole. Is there an easier way to do it other than sticking one's hand through the rear of the transmission case and fumbling around?

How does one insert the PTO assembly and get the pin into the groove per the instructions in the service manual? I couldn't quite figure that part out. Do the shifter clutch and pin need to be in certain positions, such as forward or rearward, in order to get the pin in the groove? I was looking in through the transmission fill hole, but I couldn't really see much.

Thanks for your help!

Julien

[Glen]

Hi,
Thanks for the picture.
It looks like the shaft hasn't moved to the rear, so that is good.

Good that the hole where the PTO pilot bushing goes isn't worn bigger than normal.

Be sure all the old bushing is out of the hole. The new bushing won't go in if any of the old bushing is there.

The new bushing should be tight in the hole, it has to be driven in the hole, using a hammer.
I think the post in the How To section shows using a long bolt, slightly smaller than the ID of the bushing, that will fit loosely in the bushing, threaded longer than the bushing, with a nut on it.
Put that into the bushing. The threaded end should be about even with the front of the bushing.

The bolt sticks out the rear of the housing, you can tap on the end of it there, and drive the bushing in the hole. The nut contacts the rear end of the bushing to drive it in.
Be sure to start the bushing in straight.

Put a little grease in the bushing, and on the front end of the PTO shaft, before putting the PTO in the housing.

The only way to put the PTO lever and shaft in is the way it comes out, inside the housing, and put the end of the shaft through the hole.

To put the PTO assembly in the housing, move the PTO lever, the lever that you push down to shift it, fully ahead, I don't know if you took the PTO shifter guide off the corner of the gear shifter, the PTO lever may need to go farther ahead to get the pin into the PTO clutch groove, and the end of the PTO shaft in the PTO pilot bushing.
The pin Has to be in the groove.
The PTO lever will probably go to the rear some as you put the assembly in.

Look in the transmission oil filler hole with a light when putting it together. I thought it made it easier to put it together. You can see if the pin is in the groove.