Properly sizing PTO shaft

[laurelrun]

Being a tractor newbie, I've never worked with implements that were PTO driven. Reading several threads recently about damage to PTO's, shafts, and implements due to improper sizing, I have a basic question for the board. How do you properly size a PTO shaft? As an example, if I was renting an attachment for my 855, how would I know I could use it without breaking something, assuming of course it was of a width and weight the tractor could handle. (I know I need to stick to stuff that is on the smaller side.)

[bigbull338]

Being a tractor newbie, I've never worked with implements that were PTO driven. Reading several threads recently about damage to PTO's, shafts, and implements due to improper sizing, I have a basic question for the board. How do you properly size a PTO shaft? As an example, if I was renting an attachment for my 855, how would I know I could use it without breaking something, assuming of course it was of a width and weight the tractor could handle. (I know I need to stick to stuff that is on the smaller side.)

i think they are talking about messing the tractors pto up not the equipment its running.

[JasG]

PTO driven equipment ussually has an min and max hp rating. You need to find out what those are and you and your tractor should be fine.

[Zebrafive]

The PTO shaft must be short enough to still have travel so it will not bottom out in the shortest position it will be in. This is normally when the PTO shaft is level. Mount the implement, but don't hook up the PTO shaft, raise until the shaft would be level, then see if the PTO shaft will collapse enough to install.

[yelbike]

Zebrafive has it right except for the level part. Different tractors have different lifting arcs at the three point hitch. Just look where the shaft would be the shortest point, if would you can't install or uninstall the pto shaft the its too long.
Don't take a chance with a long pto shaft!!! Been there done that, 10 k in damage to my tractor.

[laurelrun]

OK, so the dangers lie in using something your tractor just can't power and in using something with a shaft that's too long for the linkage. Thanks guys!

[PHIL850]

Be sure your Drive shaft is sized for the equipment you are running. Don't use a drive shaft designed to run a spreader on a 5' Brush hog or it might end up looking like the picture attached.

[flusher]

Be sure your Drive shaft is sized for the equipment you are running. Don't use a drive shaft designed to run a spreader on a 5' Brush hog or it might end up looking like the picture attached.

My neighbor did that number on the pto shaft inside his Ford 8N when he tried to operate an IH hay baler (small squares) without an overrunning clutch on the pto drive shaft.

[Dead Horse]

Zebrafive has it right except for the level part. Different tractors have different lifting arcs at the three point hitch. Just look where the shaft would be the shortest point, if would you can't install or uninstall the pto shaft the its too long.
Don't take a chance with a long pto shaft!!! Been there done that, 10 k in damage to my tractor.

If you do rent an implement and the shaft is cut just a tad too long, you may be able to make it work by adjusting the top link. Also, many implements have multiple holes/pin points for the lower link connections. Checking all this "fit" out is very important as you can do significant damage to the implement, PTO shaft or worse, your tractor, with too long a PTO shaft installed!

Best practice is to hook up and carefully check the fitment through the full range of motion of the lift.

[k0ua]

And if the PTO shaft is too short it can break and come apart, and if you can imagine the part that is hooked to the tractor flying around at 540 RPM in a big arc beating the he** out of anything within reach. And the other part will fly around for quite a while too. I imagine it could get pretty "sporty" back there for a while.

James K0UA