PTO shaft lenghtening

[MitchellB]

Here痴 the problem. My PTO shaft needs to be longer. I used a 5 King Kutter finish mower on my 8N tractor and had to shorten the PTO shaft to match my 8N with the overrun clutch adapter attached to the rear of the 8N tractor. Now I have an 861 Ford that does not need the overrun clutch and the PTO shaft is now too short.

The shaft/mower will work fine when rolling on the ground, but once I raise the mower, just before it reaches full height on my lift, the shafts separate.

I seem to have 4 options:
1. Weld a 2-3 extension on each shaft (cheapest and I like cheap)
2. Buy an overrun clutch to fit the 861 (not needed & a pain to take on and off as I like to keep the cover on the PTO when not using it.)
3. Buy a slip clutch (will lengthen shaft and give some slip protection)
4. Buy a new shaft and cut to fit (easiest, but I'll end up with an extra short shaft I do not need)

I知 leaning toward welding extensions which would only keep my shaft from separating if I raise it up too high, but when mowing should have no effect on the strength of the shaft.

I知 interested in hearing from some more experienced folks and their take on a solution.

 

[Indygunworks]

Sounds like you have already made up your mind? How confident in your welding skills are you? What would it hurt to try this method? Doesn't cost but pennies, and if it doesn't work you still have all the other options.

 

[kennyd]

Another option: Pto Adapter

 

[newbury]

I second Kenny's solution. TSC often has them also. I've got one for my M4700 after I put PECs on.

 

[Indygunworks]

Ill third it.... cheap price for how much headache you will save over welding... I didn't even know they made those.

 

[2458n]

TSC used to carry a even longer extension, but I bought two of them on clearance this summer. Picked up a foot in length. Seems to me that the u joint would be unsupported that far back. Will try to use mine on a baler pump.

 

[kennyd]

TSC used to carry a even longer extension, but I bought two of them on clearance this summer. Picked up a foot in length. Seems to me that the u joint would be unsupported that far back. Will try to use mine on a baler pump.

I wouldn't recommend putting two together! Get a new shaft if you need that much added!

 

[DT86]

I wouldn't recommend putting two together! Get a new shaft if you need that much added!

I agree.

 

[MitchellB]

Another option: Pto Adapter

I liked that PTO adapter idea. I did not know they made them either. I'd part with $20 or so. I started to get one until I went to place the order. By the time they added tax and shipping to me it came to over $35 or a 180 mile round trip for me if I wanted to save on the shipping. I suddenly began clutching my wallet a little tighter. I checked Tractor Supply online (which there is a store reasonably close to me) but they did not list one available.

 

[kebo]

I liked that PTO adapter idea. I did not know they made them either. I'd part with $20 or so. I started to get one until I went to place the order. By the time they added tax and shipping to me it came to over $35 or a 180 mile round trip for me if I wanted to save on the shipping. I suddenly began clutching my wallet a little tighter. I checked Tractor Supply online (which there is a store reasonably close to me) but they did not list one available.

TSC does carry them, or at least I bought my PTO "extension" from them. WHen I added the Pats Easy Change, it moved the attachment about 4" further away from the tractor, but the PTO extension added back about 4" so it works great.

 

[Sodo]

You have a welder. All you need is a good pipe size to extend it with. When you cut the shaft look for the pipe seam and make a mark on the outside, and align the 2 sections when you stick it back together.

If you have the pipe to extend it with this is a very easy job. 180 miles is 3 hours this is 20 minutes. And your welder makes money for you.

Heres another thread with info on 'timing' the u-joints. Its not critical you can do it withjust a straightedge.

 

[kennyd]

TSC does carry them, or at least I bought my PTO "extension" from them. WHen I added the Pats Easy Change, it moved the attachment about 4" further away from the tractor, but the PTO extension added back about 4" so it works great.

I searched the TSC website, but could only find a pin-on model, not a QA version like Agri-Supply sells. What style is yours?

SpeeCo PTO Extender - Tractor Supply Co.

 

[kebo]

I searched the TSC website, but could only find a pin-on model, not a QA version like Agri-Supply sells. What style is yours?

SpeeCo PTO Extender - Tractor Supply Co.

It's the quick attach style, has the spring loaded button you push in to unlock it and pull it off the PTO shaft. I bought it at my local TSC, but it's been several years, so maybe they dropped it from their product offering??

 

[k0ua]

If your shaft actually comes apart when raised, you need a heck of a lot longer shaft than you have, not just a few inches longer. PTO shafts need overlap, and the more power they are expected to deliver to the load, the more critical this overlap range becomes. If you don't have enough overlap they can easily split or "waller out" . I would buy a new shaft. And I did when faced with the same problem. If you have a press and can get the tubing out of the yokes that is another solution, and replace with new tubing. But the tubing is not exactly cheap.

Horsepower Rating and Length

if you are not sure how how far you can safely extend a driveline, the following chart give the recommended maximum extension available on each series of shaft with a minimum collapsed lenth listed. In most cases, it is recommended that the driveline does not extend 1/2 of its' collapsed length. This means the driveline tubes should should overlap at least 1/2 for safe operation at all speeds.

 

[crazyal]

I wouldn't do the PTO shaft extender. If the current length of the PTO shaft is too short and falls apart when the attachment is raised or lowered then you do not have enough PTO shaft even after you add an extender. If you do make sure you get the longer 4" version. Personally I would want 6" or more of overlap. Any money you might save will be ate by the repairs you'll be doing if the shaft comes apart. I would take the shaft to someone who makes drive shafts and see what they have that will be a tight slip over the outside of what you have now. You might be able to find something on-line.

The other option would be to see if you can find just the section of the PTO shaft you need. That's what I was able to do. My shaft was a 1" x 1 1/8" and a company called Weasler makes a replacement that has the yoke for the universal and the rectangle shaft. I think it cost me about $50.

 

[MitchellB]

If your shaft actually comes apart when raised, you need a heck of a lot longer shaft than you have, not just a few inches longer. PTO shafts need overlap, and the more power they are expected to deliver to the load, the more critical this overlap range becomes. If you don't have enough overlap they can easily split or "waller out" . I would buy a new shaft. And I did when faced with the same problem. If you have a press and can get the tubing out of the yokes that is another solution, and replace with new tubing. But the tubing is not exactly cheap.

Horsepower Rating and Length

if you are not sure how how far you can safely extend a driveline, the following chart give the recommended maximum extension available on each series of shaft with a minimum collapsed lenth listed. In most cases, it is recommended that the driveline does not extend 1/2 of its' collapsed length. This means the drive-line tubes should should overlap at least 1/2 for safe operation at all speeds.

****
From what I can gather from the charts, my 861D HP at the PTO is supposed to be 48hp, so it says 47 hp tractor should be a series 5 shaft. I have no clue as to how to tell what Series shaft my 5' King Kutter finishing mower has on it now? The shaft is triangular shaped with a twist lock connect on the tractor end. I assume it came on the mower new, but I bought this used from the original owner.

The chart says minimum of 28" with maximum of 34" (6" difference). My measurement for the shaft I need is a minimum 26.5" from the end of my 861D Ford PTO to the center of the pin hole on the mower. I'm only taking a .5" off of that and planning on a 26" cut length to give a .5" free play to install my shaft over my tractor PTO, because the mower has a wish-bone swivel connection to the lift arms than can vary the distance the mower is from the rear of the tractor several inches depending on whether the wish-bones are up (backing up with the tractor) or straight out (being pulled normally). Most places recommend about 1.5-2" gap but I think .5" will be my best bet with those floating wish-bones that can vary the distance several inches. That should give me the most overlap possible. So maybe I can go 26" to maximum of 32" with mine. I'll have to put the mower on the tractor to see what my maximum will be when lifted. The one time I used the mower behind the 861D, the shafts just did separate when the lift reached the top, but I never intend to have the mower or shaft turning when that high, but if I have to raise it that high for some reason, I don't want to have to get off and reconnect the PTO. That 26" measurement seems short compared to the measurement listed on that chart.

 

[kco]

I imagine you can size the shaft to the mower's power requirement instead of the tractor. The 5' finishing mower should not require a large shaft. A Farm King 60" recommends 12 to 30 hp for the tractor.

After adding Pat's Easy hitch I have a problem similar to yours with my 74" MK Martin Meteor snowblower. The hitch moved the blower 4" further back leaving just 2" overlap on the driveshaft. My temporary solution for this winter was to remove Pat's Easy hitch. I only use the blower in the winter and will reinstall the hitch in the spring.

My longer term plan is to replace one of the PTO shaft's triangular tubes. The 2" overlap will be OK for the shields and I don't think it will matter if the inner and outer shafts are different lengths as long as I have the minimum 6" overlap. My dealer is checking pricing and availability for me.

My shaft is a Comer Industries T50 series. The T series refers to the triangular type shaft. V series have 6 sides and E and D series are splined.

The attached .pdf gives some pages showing the ratings and parts for T series shafts. Page 11 shows ratings, 17 & 18 dimensions and 25 and 61 parts breakdowns. I think I will just need to order one of the tubes on page 61 that is 4" longer than the one I have now. I don't know if others follow the same dimensions but perhaps these dimensions will apply to your shaft.

View attachment Comer_PTO_driveshaft_P11_17_18_25_61.pdf

There is a lot of good PTO shaft information on the Comer site at:

PTO DRIVE SHAFTS

 

[MitchellB]

Thanks to everyone for the info and links. I'll compare what I got sometime to those charts to figure out at least what I have. I saw somewhere that the tri-lobbed are an Italian design.

I welded two (about a 4") sections I had saved from the drops when I cut the PTO to fit my 8N with the overrun clutch. I finished grinding my welds down today so that the shafts will slide in and out. Then mounted it back on my mower. It measures about 27.5" now, but that may be too long. I'll wait until spring when I hook up my mower to the 861D to make my final measurements before cutting to fit. I don't trust these welded splices to hold under load, but they should be fine just to keep my shafts from splitting when I raise my mower all the way up.

I'm still on the fence about getting the Pat's Easy Change, but I'll definitely have to buy a new PTO shaft if I do then.