Got a new project: Bush Hog Rotary Cutter

[Soundguy]

It's been sitting up for a probably 4 or 5 years. I know for a fact it worked fine when he parked it. I'm going to check the gearbox for leaks and make sure it works before putting any work into it. I know the PTO shaft is too short. I hooked up to it a couple years ago to use it and the shaft was too short. Maybe if I add a slip clutch to it it'll be long enough? Why shouldn't I take the stump jumper or blades off? I'd like to change the blades. If it still works good I'd like to basically do a refurb like Soundguy did with his batwing.

Nothing wrong with that either! Just check the box.. if it is good.. then work on the rest. For not much money.. but quite a bit of sweat.. it ought to looknice.

I'm heading out to mow with my 'perty JD1517 in about an hour... Hope to get 10ac cut inbetween rain.

Soundguy

 

[kc5dlo]

Might be an optical illusion, but in 1 of the pics it looks like the cutting tip of one of blades is lower than the other.

 

[jwstewar]

Might be an optical illusion, but in 1 of the pics it looks like the cutting tip of one of blades is lower than the other.

I see that too. It looks like the front blade is bent down away from the deck.

 

[Renze]

Yes one of the blades is sloping down, you guys must be right...

I assume it's just one blade suspension bolt that needs tensioning. I worked on a 30 year old Woods bushog when i was in Canada 2 years ago, both blades were curved like bananas, allways digging up dirt. They were also cracking around the suspension bolt holes... it was too dangerous to keep using it so we put it aside untill new blades were found.

I want to build a bush hog from the angle drive of my old Claas drum mower... You can only get roughland mowers new in Holland, there are no used ones for sale. I kept the old drum mower to mow under fencerows, where i dont want to stress my new Krone disk mower for, but a bush hog type mower with heavy machetes will be of more use to cut brush...

 

[Jarrett]

I got a few more pics of it. I got all the leaves cleaned of and some of the rust scraped off. Overall I don't think it's too bad. I have a little patching and welding to do. I think I'm goint to replace the 2 pieces of angle iron that the gearbox mounts to. They're in pretty bad shape. I think I'm going to add some more bracing to the 3pt. frame and convert it to captured lower link pins. I'm going to patch the deck where needed. I've changed my mind about being in such a rush to paint it. I'm still going to sandblast it and repaint, but I'm just going to wait a while for that. I'm going to get the structural repairs done and make sure it works. I have it covered with a tarp and sitting on blocks, so at least it's out of the weather mostly. The pto shaft is too short by a couple inches and the u-joints are frozen, so I'm going to get a new one. I would get that ASAP so I could try it out, but I found that the bolts holding the gearbox have no heads left. The heads are all rusted off along with the angles it's mounted to, so I need to rapair that before putting any torque to it. I opened the gearbox an it looked like it had grease in it. But it could have been really old oil that got overheated and sludged up maybe? Anyhow, I'm going to take some WD40 or something and try to rinse it out a little and put oil in it to check for leaks.

 

[Jarrett]

As for the blades...they're not bent. They're not too bad, except for having been sharpened quite a few times. The ends are rounded pretty good and alot of material has been removed. They do have a good bit of slack on the pins though. Is this a really bad thing? Could it be the blades are worn out or the pins? Maybe the pins aren't tight enough? Anyhow, I need to remove the gearbox anyway to repair the mounting, so I need to get the stump jumper off. One big problem though.....someone welded the nut on. It's a pretty crappy weld job and it's basically just tacked so I'm hoping I'll be able to grind enough off to get it loose without too much damage.

 

[Jarrett]

Just a few more pics. When I finally got the pto shaft off, I found the input shaft of the gear box has a half-moon slot keyway. I wasn't expecting this. There wasn't a key or anything in it. I figured the shear pin was the only thing it used. Is there supposed to be a key in there? Does it shear too? The shaft was difficult to get off because he had a grade 5 bolt through it. It wasn't even large enough diameter. The bolt had bent so I had to pound it back straight then pound it through the hole. Fortunately the hole in the input shaft wasn't damaged.

 

[Soundguy]

Keep the progress reports coming. Pics are great.

Soundguy

 

[Soundguy]

Just a few more pics. When I finally got the pto shaft off, I found the input shaft of the gear box has a half-moon slot keyway. I wasn't expecting this. There wasn't a key or anything in it. I figured the shear pin was the only thing it used. Is there supposed to be a key in there? Does it shear too? The shaft was difficult to get off because he had a grade 5 bolt through it. It wasn't even large enough diameter. The bolt had bent so I had to pound it back straight then pound it through the hole. Fortunately the hole in the input shaft wasn't damaged.

If the round smooth shaft had a hole and a key way.. then the gear box was setup for either a slip clutch which would have used the keyway ( though some do pin on ).. or the plain driveline and shear pin.

Soundguy

 

[sandman2234]

That would be a woodriff key, but a "shear pin", I don't know. It is a duplicate of what is used in lawnmowers to protect the crankshaft. They sell them made out of aluminum for small lawnmowers, but I don't know if they are available in aluminum for bush hogs. Might be a question for "Bush Hog"!
I think I would invest in a clutch, or leave the woodriff key out, and just use the shear bolt. Go back to a grade two and go from there.
You can extend your existing pto shaft if you are a reasonable welder. If not, find someone who is, or replace it. I have found a couple new shafts on ebay for less than $60 complete, so keep an eye out on that. Adding a slip clutch to it might give you the length you need as you mentioned.
Holding off on the paint till after you get it mechanically sound is the right way. You will make a mess out of it when that lower seal gives way (and it will if you paint!)
Somebody might have already replaced the gearlube in the gearbox with grease due to that seal leaking... Grease doesn't require nearly as tight of a seal contact.
A little use will also make your job of sandblasting easier. The sand and grass and brush will knock off a lot of rust!
Do what you can to make it run, before spending a lot of money on it, and you will make your wife a lot happier, which will allow you to butter her up next time you want or need something for the tractor.
David from jax