Ford 8n leaking PTO w/ possible broken overrunning coupler

[nrbocke]

Hi everyone-
I have an 8n (52 or 53) and the PTO developed a pretty good leak pretty much out of the blue. So I've read some posts and it sounds like a few guys just had material wrapped inside the PTO causing issue. So I wanted to inspect that first.
I have a overrunning coupler from TSC that I needed to remove. The roll pin was broke in half. Don't know if I broke it removing it but I think it was already broke inside. A very small spring came out also. There was some foreign material and the overrunning coupler but not much.
Cleaned grease and oil off PTO and no material found wrapped around PTO. So I've cleaned up the floor where oil missed my bucket, laid out clean shop towels, and about 24 hours later no leak.
So I guess I was just wondering if anyone thinks the overrunning coupler/roll pin caused the leak? Also anyway to test the overrunning coupler before I reinstall it our buy a new one? I'm guessing the little spring that fell out is needed for something?
Thanks for any thoughts!

 

[Ultradog MN]

Just a guess here.
Often when a guy adds an ORC onto the pto shaft the driveshaft of the mower is then too long.
When you lift the mower up the the driveshaft is pushed forward. If it is too long it will force the pto shaft into the tractor and break the circlip that holds the pto bearing in place and cause an oil leak .
Drain the oil from the rear end and remove the 4 bolts that hold the pto in. Pull the pto shaft and inspect the circlip.
Too long a drive shaft is likely what caused the roll pin to shear too. Means you bound the ell out of it.
It is a simple repair. Like on a scale of 1-10 with 1 being an engine oil change and 10 being an engine overhaul it is about a 2.
When you get the bearing and seal fixed connect the mower back up to the tractor without the drive shaft connected and measure the distance between the gearbox on the mower and the pto shaft while the mower is halfway raised. Then take a sawzall or even a hacksaw and cut an equal amount off both halves of the drive shaft so it doesn't bind when you lift the mower. Easy does it. Don't cut too much. Better to cut it 3 times than have it too short. They are expensive to replace.
You want about 1/2-3/4" clearance at it's shortest point.

 

[nrbocke]

Just a guess here.
Often when a guy adds an ORC onto the pto shaft the driveshaft of the mower is then too long.
When you lift the mower up the the driveshaft is pushed forward. If it is too long it will force the pto shaft into the tractor and break the circlip that holds the pto bearing in place and cause an oil leak .
Drain the oil from the rear end and remove the 4 bolts that hold the pto in. Pull the pto shaft and inspect the circlip.
Too long a drive shaft is likely what caused the roll pin to shear too. Means you bound the ell out of it.
It is a simple repair. Like on a scale of 1-10 with 1 being an engine oil change and 10 being an engine overhaul it is about a 2.
When you get the bearing and seal fixed connect the mower back up to the tractor without the drive shaft connected and measure the distance between the gearbox on the mower and the pto shaft while the mower is halfway raised. Then take a sawzall or even a hacksaw and cut an equal amount off both halves of the drive shaft so it doesn't bind when you lift the mower. Easy does it. Don't cut too much. Better to cut it 3 times than have it too short. They are expensive to replace.
You want about 1/2-3/4" clearance at it's shortest point.

Thanks for the idea. Seems logical. If I'm not losing any fluid after a week do you think I should still drain it out and check the circlip? As of Sunday everything was dry and my fluid level was still ok.

 

[Ultradog MN]

If it is not leaking now then I would still check/adjust the length of your drive shaft as explained above. Too long can damage both the tractor and mower.
Then run it. If no leaks you're good to go. If it leaks you know you damaged the circlip and/or seal and can fix it then.

 

[nrbocke]

If it is not leaking now then I would still check/adjust the length of your drive shaft as explained above. Too long can damage both the tractor and mower.
Then run it. If no leaks you're good to go. If it leaks you know you damaged the circlip and/or seal and can fix it then.

Sounds like a good plan. Thanks!