8N Ford pto ?

Fri May 16, 2014 6:57 pm

My 8N Ford pto will not stay engaged under load . The problem occurs more often as rpm is increased. It has the original 1 1/8" shaft. This condition just developed as I was raking hay. Just checking to see if anyone else had experienced this problem and how you solved it.

Thanks, Berlin

Re: 8N Ford pto ?

Sun May 18, 2014 5:10 am

At the end of the shift rail on the pto bearing support there is a nut with a lock washer. Sometimes this can work loose and the ball will not fully engage in the groove. It could also be the grooves on the shift rail are worn or a flat spot on the ball or weak/broken spring or the lever to engage the pto could have some wear. I would look at that first before tearing the whole thing apart to look at the sleeve or bearing. Your FO-4 shop manual should have a photo unit.
I would check the lever where it engages the shifter rail by just taking the round side cover off. Unless your oil is low it should come up to the lower holes on the side cover so will need to be drained. If that's ok I would see if the nut at the end of the shifter rail is loose. It has been a while since I worked on the 8n but I think you can tighten that nut by working with a cut or stubby wrench. I know it's easier to just pull the pto shaft and drop the pump for better access. If the nut is tight I would loosen it and rotate the shifter rail 180 degrees and retighten. The groove detent goes all the way around the shifter rail so basically you just want to move it out of the worn spot.
See if this solves your problem. This is the easy stuff to try before getting into the whole system. I should mention that your trans/hydro/rear uses all one system so when you drain one you are draing them all, about 5 gallons worth.
OR as some guys have done,duct tape a bungee cord to the pto lever to hold it in place. Don't use vise grips to hold the bungee on cause when they fall off they make quite a racket hitting in the bushog and can shoot out the back like a rocket.


Re: 8N Ford pto ?

Sun May 18, 2014 12:07 pm

Thanks for your suggestions , I will check those parts. I do appreciate your help.