Removing PTO driveshaft from RC

[Pooh_Bear]

I guess anything is possible before I got it.
I got the tractor with the brush hog attached.
Just like it was. If it was different before that I don't know about it.

It will be fixed right when I put it back together.
I rarely use the thing anyway. It looks to have had a lifetime of abuse.

Pooh Bear

 

[Soundguy]

Wrong key material?

Soundguy

Then why didn't it shear when I ran it up to full throttle
and dropped the brush hog on a stump. It sure stopped the engine.
I did this 8 to 10 times before I gave up. Hope I didn't damage the tractor.

When I was drilling out the bolt, when I got to the woodruff key,
I had to keep sharpening the drill bit. I think the key was hardened.
Otherwise I should have been able to drill thru it easier than the bolt.

Pooh Bear

 

[Pooh_Bear]

For me to put it back together like it was I will have to re tap the threads
in the hole where I drilled out the bolt. I drilled out threads and all.
It does have a place for shear pin, so I'll try that first.

Pooh Bear

 

[Soundguy]

I'd think a shear pin will be way more user serviceable in the future.

Besides.. if you did go back with an aluminum key, chances are the bolt you use to retain it may rust and have to be drilled back out again anyway.. unles you are lucky..

Soundguy

 

[SPYDERLK]

I'd think a shear pin will be way more user serviceable in the future.

Besides.. if you did go back with an aluminum key, chances are the bolt you use to retain it may rust and have to be drilled back out again anyway.. unles you are lucky..

Soundguy

You can use a stainless steel bolt - or better a gr5 with loctite. The loctite will seal the thread and prevent rust while holding the bolt in place. To loosen use heat to soften the loctite.
On another note - - the tractors PTO clutch protects the tractor. The shear pin protects the implement.
Larry

 

[Soundguy]

The only issue I see is that the hole is not blind, thus, rust could start from the ID of the yoke, up the bolt hole, seperating the loctite from the parent metal. If I went that route anyway.. i think I'd go grade 5.. the stainless seems to gall way too much, use the never sieze.. and coat it liberally, and then use a lock washer right under the bolt head. I'd also grind the OD of the yoke where he bolt is to make a small 'flat' .. etc. Of course this is all academic, as he stated there was a shear pin hole already in existance.. etc.

I'd want more protection for my tractors tranny than the tractors pto clutch. I've seen plenty of twisted and broke pto shafts... Way easier to punch a grade 2 bolt out and replace, vs replacing a pto shaft...

Soundguy

 

[SPYDERLK]

Soundguy. The telescopic PTO shaft was too weak. You wont see a twisted 1-3/8 spline. The PTO clutch is sized consistent with the tractor strength and the spline is OEM.
A joint filled with loctite is sealed from both sides.
Larry

 

[Pooh_Bear]

We're talking about a 1949 8N tractor here.
PTO was upgraded to the modern 1 3/8 size last year.
But on a tractor that old, anything is liable to be a weak point.
I'll be going with a shear pin when I put it back together.

I use nail polish on the threads instead of loctite.

Pooh Bear

 

[Soundguy]

Soundguy. You wont see a twisted 1-3/8 spline. The PTO clutch is sized consistent with the tractor strength and the spline is OEM.
larry

I can, and have seen pto stubs twisted, and snapped off. i have seen pto shafts twisted int he center, I have seen them twisted at the tranny countershaft connection point.

The OEM shaft for an 8n was 1 1/8 On the upgrade shafts, only the stub end, after the bearing is 1 3/8 I.E.. the stud end is larger than the driving shaft.


I couldn't begin to tell you how common it is for an N owner to have to take a hacksaw or sawzall or torch to the center section of his N to cut the pto shaft before and after the pto pump, then drop the pump, drive the slug out, and then wrestle the twisted splines out of the pto sliding coupler dog.. All from using regular sized and correct equipment, and simply no Good pto protection. In a tractor with a single stage clutch, and non-live pto, the main tranny clutch is the only clutch in the system.. there is no 'pto' clutch.. The main system clutch is rated at higher hp then the pto.. also keep in mind that on a tranny driven non live pto, it is very likely that the pto and the rear drivetrain are locked as long as the tranny is in gear.. thus rolling inertia can power the pto even if the clutch is pushed.

Frankly.. your comment does not apply the way you think it does, in this situation.

Soundguy

 

[SPYDERLK]

Soundguy, Good explanation. Ihad heard about that type of arrangement but I didnt know what kind ot tractor to attribute it to. I can see how that would be a major problem for the tractor unless external protection was provided. My tractors only go back to '62 and have PTO clutches. I find that at the limit they either break, or protect themselves from anything they are hooked to. I like that feature.
Larry