How can I adapt a PTO shaft from the standard 540 to a 15 spline

[amanda11270]

I have a compact Bolens Iseki tractor that has a 3pt hitch, it has the standard 6 spline pto shaft, how can I adapt it to run a 15 spline snowblower on the rear of my tractor, do they make a adaptor? Its a Gravely blower and 15 spline must be Gravelys PTO size. I guess im looking for a shaft that goes from 6 spline to 15. Where can I find it if its even available.

 

[LD1]

I did a quick google search and didn't turn anything up.

Your best route to take would be to replace the yoke on the tractor end with the standard 1-3/8" 6-spline.

If you can get some measurments on the size of the u-joint fot that yoke (u-joint length and diameter of the caps) you can probabally take it to a place like TSC and match one up.

Here's some examples. They make several sizes

Splined Bore Yoke, 6N - 0270003 | Tractor Supply Company

Splined Bore Yoke, 12N - 0270184 | Tractor Supply Company

Splined Bore Yoke, 35N, 6 Spline - 0270435 | Tractor Supply Company

 

[greg_g]

What you might want to try first however, is consult the appropriate Gravely manual to determine input requirement (in RPMs). Six spline PTO components are typically designed for 540 rpm operation. A greater number of splines generally suggest a PTO operating speed of something greater than 540. Say 720, or 1000 - or even 2000 in the case mid PTOs. What I'm trying to say is that- given the 15 spline coupler - your Gravely might not be a 540 rpm machine in the first place.

//greg//

 

[gwdixon]

See if one of these would work.

Agri Supply - Search

 

[SPYDERLK]

Ordinarily the fine spline shaft is 21T. Those adapters are readily available. What uses 15T
larry

 

[Poyjas]

I just picked up an MTD Products 40-inch rototiller. I haven't been able to track down any info on it yet. It does have a 15-spline 1-inch diameter (female) jackshaft that needs to connect to the 6-spline 1-3/8 inch pto shaft. I'd prefer an adapter if anyone's found one. I have a Kubota B7100HST-D. Thanks!

 

[Knight]

It might be hard to find that kind of adapter.
Might be easier to find a 1 3/8" adapter to smith keyed shaft( I just bought one from agrisuppy) And then find a 15spline to shaft adapter. Buy a short pice of smith keyed shaft, cut it and stick the adapters back to back with the keyed shaft inside. Set screw.

or maybe look for a speed reducer gear box.

 

[klink]

In the late 60s, 70s, 80s & early 90s larger models of Simplicity, wheelhorse, John Deere, Bolens, Power King & others all had a 2000 rpm - 1" 15 spline pto. Even if you buy or make an adapter, your snow blower or rototiller rpm may run extra slow because it was engineered for a 2000 rpm input not 540 rpm.

 

[kevinj]

What you might want to try first however, is consult the appropriate Gravely manual to determine input requirement (in RPMs). Six spline PTO components are typically designed for 540 rpm operation. A greater number of splines generally suggest a PTO operating speed of something greater than 540. Say 720, or 1000 - or even 2000 in the case mid PTOs. What I'm trying to say is that- given the 15 spline coupler - your Gravely might not be a 540 rpm machine in the first place.

//greg//

What he said. My odd splined stuff is all high speed.

 

[Knight]

Maybe you can make a pulley set up to get speed back and take care of the spline difference problem at the same time.