PTO Shaft - OK if I'm 3/4" short?

[rossn]

I have a MF GC1705 that I recently purchased, and am looking to buy a used tiller. I located a King Kutter XB, in good shape I am considering, and the owner removed about 1" off the original PTO shaft. Using the video by (Temporarily blocked due to reports of company closure) at: How to Measure and Cut a Tractor PTO Shaft - YouTube I find that the PTO shaft is probably about 3/4" too short (gap between PTO shaft and tractor's output shaft will probably be 2.75"), based on the 2" gap recommendation.

Is this a safety issue that would require me to buy a new PTO shaft?

Thanks,
Ross

 

[RickB]

Tillers are sketchy due to the short shaft that seems to be on all of them. If you can maintain about 6" of shaft overlap between the inner and outer halves and not have the halves bottom out through the lift range of the hitch, you should be OK.
I didn't watch the EA video and probably won't, so I can't speak to how it describes the issue.

 

[jeff9366]

If the PTO shaft separates, the tractor half becomes a tractor powered lethal flail.

This would be a critical issue with Rotary Mowers, which are run over banks and into swales.

Less so with roto-tillers which are mostly used on level ground at low speed, therefore the PTO shafts extend and shorten less.

 

[RickB]

If the PTO shaft separates, the tractor half becomes a tractor powered lethal flail.

Not likely to be lethal, just expensive when a tractor's internals get torn up.

 

[KYErik]

You could buy a PTO extension adapter that would slide over the tractor PTO stub and give you an extra 5" of overlap.

 

[smstonypoint]

Here's an adapter that increases the PTO shaft length by 1 1/8": SpeeCo PTO Short Increaser - For Life Out Here

Steve

 

[rossn]

Thanks, KYErik and Steve! Is that generally considered an 'acceptable' solution for type of an issue. I recognize they sell them, but wasn't sure if something like that can lead to other issues, such as with the bearings? At 1 1/8: extension, it is pretty short, which is good.

 

[oosik]

I didn't watch the EA video either. When I check a PTO shaft for proper length - I do it this way. Hook up the implement to your 3-point hitch WITHOUT connecting the PTO shaft. Separate the PTO shaft into its two halves. Hook one end to the tractor PTO stub and the other end to the implement. Hold them up together - side by side. Now have another trusted individual raise/lower the implement SLOWLY thru its entire range of up/down motion and see if the shafts will still have, at least, a six inch overlap and will not bottom out. As long as there is still a six inch overlap thru the entire range of motion and the two shafts will not bottom out on each other - you will be OK.

If the overlap becomes less than six inches - you have the wrong PTO shaft and need a longer one. If the shafts will bottom out - you will need to cut an appropriate amount off each end of each shaft. There should always be at least two inches "leeway" before the inner/outer halves will touch.

I have never seen nor used any type of extension adapter so I can not comment on that.

 

[gwdixon]

Agree with the others about the critical nature of the overlap. Six inches is good, four inches is pushing it.

As mentioned, separate the shafts and measure both shaft sections. Add the measures together (A + B = C). Then put the shaft back together and attach the implement and the shaft to the tractor. Measure the resulting shaft link all hooked up. Call it measure "D". C - D > 6" if it is to be totally safe.

Then raise the tiller and measure the shaft length. This is where the shaft is usually extended the most. There should be at least 4" of engagement fully lifted.

Those of us that use Pat's Easy Connect deal with the issue often.

 

[newbury]

Don't forget to check the length with the attachment well below the horizontal if there is any chance this will occur in real life.