Mahindra PTO seal keeps coming out

[Captainde]

I have a 4540 mahindra tractor and I just put a new PTO oil seal in the rear and in about 2 hours it pulled out and I lost most of my hydraulic fluid. Anyone else having this problem? Would love some help on how to fix it. In the illustration its part number 20. I replaced the gasket and also the PTO oil seal retainer(part 17)

 

[loggin]

I have a 4540 mahindra tractor and I just put a new PTO oil seal in the rear and in about 2 hours it pulled out and I lost most of my hydraulic fluid. Anyone else having this problem? Would love some help on how to fix it. In the illustration its part number 20. I replaced the gasket and also the PTO oil seal retainer(part 17)

Perhaps you could provide us with some better photos of the pto. Hard to tell what's going on there. Do you have Part #17 installed properly? It looks like it is supposed to retain the seal.

 

[Captainde]

Here are 2 pictures of the PTO and seal on the tractor. You can see the seal has come out and I got it this far back in to stop the leaking trany fluid. The other pictures are of a new oil retainer and oil seal. I bought 2 when the leak happened and these are the ones I have not used. The one on the tractor has 3 hours on it. Itg was brand new yesterday.

 

[Harry in Ky]

A few possibilities come to mind. Transmission case pressure? Have you located and checked the vent for the main housing? Not necessarily a common problem but you can't rule it out without checking. Another is the seal itself. Is this a mostly rubber backed seal without a metal jacket on the outside where it fits into the bore in the retainer? It looks to me like it might be. That type typically fit looser than the others, and are more prone to walk out. If that's on the list you might consider crossing it over to a different brand with the same inner and outer dimensions. Another option is to fabricate something that will bolt on (maybe using the three pictured retainer bolts) that will forcibly retain the seal in place. I've had to do that before in certain cases.

 

[loggin]

Here are 2 pictures of the PTO and seal on the tractor. You can see the seal has come out and I got it this far back in to stop the leaking trany fluid. The other pictures are of a new oil retainer and oil seal. I bought 2 when the leak happened and these are the ones I have not used. The one on the tractor has 3 hours on it. Itg was brand new yesterday.

Not sure but it looks like the seal may be installed backwards. There is a small channel towards the inside of the seal near the shaft. This channel is supposed to be on the oil side in order to produce some pressure against the shaft.

Thanks for including some better pics!! Kind of hard to see the seal though with it still in the plastic. There might be some shoulders on the seal that align better with the retainer depending on which way the seal is installed as well.

Just trying to understand what's going on a bit better.

 

[DarkBlack]

I’ve seen oil seals work their way out on machines where the shaft was was not concentric with the seal bore hole. Double check that your’s is, and that the shaft runs true.

As previously mentioned, hydraulic pressure would contribute, but not by itself. Make sure your breather is functioning.

You can use a cylindrical retaining compound like loctite 641 on the seal.
It won’t fix the cause, but should help keep the seal in place.

 

[ruffdog]

What type of breather vent does it have? Sometimes they get plugged by mud daubers then pressure pushes the seal out.

PTO seal leaking

 

[Captainde]

A few possibilities come to mind. Transmission case pressure? Have you located and checked the vent for the main housing? Not necessarily a common problem but you can't rule it out without checking. Another is the seal itself. Is this a mostly rubber backed seal without a metal jacket on the outside where it fits into the bore in the retainer? It looks to me like it might be. That type typically fit looser than the others, and are more prone to walk out. If that's on the list you might consider crossing it over to a different brand with the same inner and outer dimensions. Another option is to fabricate something that will bolt on (maybe using the three pictured retainer bolts) that will forcibly retain the seal in place. I've had to do that before in certain cases.

I replaced the breather vent and even drilled the orifice alittle bigger to reduce the backpressure and that did not work.

 

[Captainde]

Not sure but it looks like the seal may be installed backwards. There is a small channel towards the inside of the seal near the shaft. This channel is supposed to be on the oil side in order to produce some pressure against the shaft.

Thanks for including some better pics!! Kind of hard to see the seal though with it still in the plastic. There might be some shoulders on the seal that align better with the retainer depending on which way the seal is installed as well.

Just trying to understand what's going on a bit better.

I replaced the seal again and reinstalled it and in about 2 hours it walked out again. I even put some JB weld on 3 points to try and hold the seal inplace. no luck.

 

[Henro]

I replaced the seal again and reinstalled it and in about 2 hours it walked out again. I even put some JB weld on 3 points to try and hold the seal inplace. no luck.

Might be time to check the shaft to ensure it is running true, as suggested by DarkBlack in post #6.