PTO issues
 

I had posted on Wayne's thread, not meaning to hijack it, so I thought I would create a new thread.

I depend on you experts here with helping out this greenhorn here on my PTO issue.

I was mowing my mother-in-law's large property yesterday and started smelling something like burnt clutch or breaks. There was a white puff of smoke coming from the front of my 128. I decided to disengage the PTO and it would not disengage. The blades kept turning under the mower, no matter what position I had the PTO handle in.

After the engine cooled off, I looked at the PTO assembly. I understand the basic premise of operation, yet I have no idea if anything I was looking at jumped out at me as the cause for the failure. I decided to take some pictures and show you guys to see if anything jumps out at you as the "smoking gun", pun intended. What should my next steps be?

Thanks in advance to the great members of this forum!

[EDIT]
The first picture is obviously with the pto lever cotter removed to allow the brake assembly forward.
The second picture is with pto lever disengaged
The third picture is pto lever engaged.
The last picture is a side shot, doesn't look like brake assembly is square with pto, is it supposed to be?

With the brake set as it is in you picture #1, can you see or feel the thrust button as it is in this pic?

Yes, I see the thrust button.

So, what have you done to diagnose this thing??
Have you checked the PTO lever adjustment?
Have you pulled the belt and checked the pulleys to see if any of the bearings are out of them?
We don't see anything either. Not really anything to look at on a PTO. All the components are internal and can't be seen. Can't see the spring, or the disk, or the levers.... so, not much to look at.

Check the rod adjustment and see if it is correct before you go jerking the PTO off.

Stop it, I'm getting excited.

OK, it doesn't look that great but at least it's there. A new one looks like this....on to next step....

:OhOh::OMG:

............

Thanks ironman.

I tried rotating the belt with pto enabled and disabled, no difference. Of course, the pto brake may be causing me issues? But the belt wants to rotate the engine no matter what position I have the pto lever.

I am looking for a rebuild kit for the front PTO. I have seen several on ebay, but none for a later brake pto; they are all older push pin rebuild kits. If I am going to tear this thing down, I am going to put it together right. I am sure it has never been touched since built in '73...

The brake pad on the pto looks pretty low too. I have seen replacement pads, but no instructions on how to replace. I am assuming scraping the remnants of the old pad off and jb welding the new on? I dunno, what have others done?

Next let's look at the pivot screw/bolt that holds the brake shoe to the release arm. It is kinda cone shaped and sits in the bowl section of the brake shoe. We are concerned about the head as that is what presses on the thrust button when you disengage. If you can remove the nut and spring to get the shoe off of the release arm, take a look at the hole in the shoe that the pivot screw goes thru, make sure it is not all wallowed out. That could be why your shoe does not look perpendicular with the pulley. Pictures of new pivot screw and brake shoe.

To turn the PTO pulley, loosen the belt tension at the mule drive and take the belt off the PTO completely. It will be easier to make adjustments. Then set the handle to the disengage and see if the pulley moves. If not at first, try tightening your turnbuckle to see if anything changes.

Awesome! I will try that out in the morning. Thanks again ironman!

Checked all the clearances between pto brake and pto, all looked good. Started the mower and after about 60 seconds of running, heard a loud grinding at the front. Stopped the engine immediately and saw my pto had started coming off the front of the mower.

Pulled the pto and found the problem. PTO driveshaft bearing had failed inside the pto. Inner part of bearing is still on driveshaft, outer part of bearing is still in pto; loose bearing everywhere. Glad the belt and brake held it on without it flinging out of the mower and potential causing more damage to mower or myself.

Now that I know my problem, I have ordered a pto master rebuild kit and will begin the rebuild when it arrives. I am keeping my fingers crossed that the drive shaft wasn't damaged during this failure.

Thanks everyone for your help, but this is what a critical pto failure looks like...

P.S. If there is interest, I will update this thread with my rebuild of the pto with pictures. Any comments are more than welcome!

I told you in post #6 to check the bearing.
We've all seen this type of failure. No need to document it. Has to be 100 PTO rebuild threads on here.

Considering this is my first Cub and I had only had it a week. You might as well have been speaking Klingon. I appreciate the advise.

Gotta watch dem klingons,
they come from yuranus. :biggrin2: :biggrin2: