PTO

[Mike H]

Hello All,
I recently was given a agri four 48 inch rotary cutter. I need to know if I buy new PTO shaft does it have to be cut or can it be left long. The one i am looking at goes from 42.5 inches to 55.3 overall safe span. The one that is currenly there is actually about 4 inchs short and if I remember correctly its been cut to 45 inches. I just need to know if I can find one a little shorter. The one I have is 1 3/8 6 spline and 1 3/8 smooth on the attachment with 1/2 inch shear bolt. Does it realy need to be cut or can it be used at that length? This is the one I was looking at.

PTO Shaft - PTO Shafts

PTO shafts rotate in motion to transfer energy. This series 4 PTO shaft has a retracted overall length of 42.5 in. and an extended safe overall length of 55.37 in.

www.agrisupply.com

Thanks
Mike

 

[85Hokie]

if you cut.......... you must both ends!!!

Too long will break rear diffy if it bottoms out against the tractor - and two short will have just as bad consequences

 

[Dieseldonato]

If it doesn't bottom out it will be fine. You can hook up your implement and get a rough measurement of how long of a shaft you will need. Better to have to cut one down a few inches then have to buy another one because it wad too short.

 

[NCL4701]

Agree with Dieseldonato. Hook it up without the shaft, measure at its closest point throughout range of movement (both lift arms and toplink) to make absolutely sure it can’t ever bind (which can cause totally unacceptable amounts of damage). If you can get one the right length off the shelf, swell. If you need to cut it down, that’s a pretty easy job. Just watch a YouTube video or two and have at it.

 

[Russell King]

Explain why you think it is 4 inches short?

There has to be some overlap between the two halves at the worst condition (least amount of overlap) but does not need to be completely overlapping at its shortest position.

There are many resources that explain how to size the pto shaft so you may want to search for them on the internet (I don’t want to provide bad information on such an important part)

 

[mcfarmall]

I've seen on some mfgrs websites that they recommend a minimum of 9" overlap when extended. My rule of thumb is 9" of overlap when extended and enough clearance to uncouple the PTO when retracted.