Snow driveshaft from mid pto to front pto on 790 keeps detaching when using 59" snowblower

[rog1]

driveshaft from mid pto to front pto on 790 keeps detaching when using 59" snowblower

I've owned the JD790 for 12 years and the 59" snowblower (front mount) for 9 years. Never had a problem til this winter, but now have had the attachment collar in front of driveshaft that connects the front ujoint to the front pto let go and allow driveshaft to detach. Net result has been a complete disassembly of the attachment collar and severe damage to the collar itself? anyone else experience this problem? Solutions?

 

[Tx Jim]

Re: driveshaft from mid pto to front pto on 790 keeps detaching when using 59" snowbl

Have you lubricated the 3 balls so they seat into the depressions on the tractor pto shaft well? Are the depressions(notches) in good shape and not worn?

 

[rog1]

Re: driveshaft from mid pto to front pto on 790 keeps detaching when using 59" snowbl

yes-first thing I thought of-I'm thinking of tapping out the holes where the bearings seat and installing allen set screws in place of the ball bearings. Seems a lot cheaper than replacing the attachment collar and ball bearings although it will be a pain installing the front end of the driveshaft , but I only do that once each fall in prep for snow removal.

 

[Tx Jim]

Re: driveshaft from mid pto to front pto on 790 keeps detaching when using 59" snowbl

Before I disassembled and tapped the holes and insert set screws I would clean & lubricate the balls very adequately and try it

 

[Chooglin]

Re: driveshaft from mid pto to front pto on 790 keeps detaching when using 59" snowbl

I had the same problem with the PTO shaft on my MMM and this is how I cured it.
I drilled and tapped a hole in the casting to screw a bolt and lock nut in it.
this will prevent the collar from reliesing the balls.there is no way for it to come
off unless the bolt backs out.