Our PTO driven wood chipper will shear the pin if you engage the PTO above idle. You learn in a hurry to keep the rpms down when starting up. Tractor Supply will have grade 2 bolts for cheap. Get yourself a bag of them.
Took a pic of the busted bolt-
Here’s a pic of my scoured clean double bottom. After a few passes in the turf it looks like new, sort of. And here in the barn it will sit for another year…
Nice Dearborn! Is that a 12", 14" or 16"? Mine is a 12" (10-152) so I can’t get parts for it. I’m having a hard time getting it set up right, it won’t roll over the sod/soil. I’ve watched what I can find on YouTube and set it up according to what they show, but no luck. We just bought a '68 Ford 5000 and it came with a two-bottom John Deere plow that I hope to rehab and get better results with.
Thanks. Yes, it’s a Dearborn, the model number is a 10-156, I think it’s a 14in. I got it two years ago, right after I got the John Deere. When we got here on the farm four years ago, there was already this bush hog, and a disk harrow, but no plow. So, I got to looking on Craigslist, and found it at a used farm equipment place about 40 miles from here. They wanted about $300, but it think I paid $250. I think that was a fair price, considering how hard they are to find in that condition.
I was a tractor noob, so I knew nothing about them, thankfully my bro in law does, and passed along a lot of good info, and helped me out. But, I had to learn how to set up the plow myself through a lot of internet videos and articles.
We have about a 3 acre pasture that isn’t used for anything, but it’s cleared off, so I used it as a training ground. It took a lot of trial and error, and I did a few plowing runs until I felt confident enough to do it for our garden plots.
It is tricky, you have to manipulate the top link, and the right lift arm lever to get it where you want it. I set mine up by getting on level ground, and lower the plow down to the ground. I want the tips of both boards or shares, whatever they’re called, touching the ground at the same time, at a very slight angle. That is, I want the tips touching before the back of the share, maybe an inch or two lower than the back of the share.
Usually I do this by sitting the plow down on the ground and adjusting the link arm, and then lifting it back up until the tips look level. To get the share angle right, I pull in the top link by giving it a few turns. The shorter top link will pull the plow towards the tractor, and should give you the proper angle. I’m now ready to do my first run.
Depending on the slope of the hill, I want to throw the turned soil up the hill. I always plow across the hill, not up and down. If I’m sitting in my tractor, and the hill is sloping from right to left, I want to make my first run on the right side of my proposed plot. A key to getting the sod turned over, is to get up enough speed. I tried to do my runs at about 4mph, which for me was in low 4th gear.
After the first run, you drive your right tires into the newly cut furrow, and you’ll notice your plow is no longer level with the ground, because your right side is down in the furrow. So you have to get out, and readjust the right link, usually to pull it up to make both share tips level with the ground again.
After the readjustment, you’re ready to make the rest of your runs, while in that furrow. If you have multiple plots to do, I do the first run on the right side of each plot, then do my in-furrow adjustment, and finish the plot, and move on to the next plot. It sounds a bit complicated, but after a while it becomes easier. It’s still a bit of an art too, so some folks may do it a bit differently.
One other thing on the shear bolts. Sometimes they get old and just shear easily. They are soft metal so they wear a bit under normal use and eventually get a little weak.
The biggest problem with shear bolts is that sometimes the shaft will rust on the gear box and then the shear bolt won’t shear properly, and instead break the box.
That said, those gear boxes are pretty tough, if it’s a decent mower. Plus if it has a stump jumper underneath (as it sounds like yours does) the blades will just bounce off big rocks and stumps.
I once had someone bush hogging for me and they hit an 6" steel well casing. The wall thickness was about 1/4" steel. It made a heck of a racket when it hit and nearly “mowed” the well casing off. The mower made a little bit of bearing noise after that, but it was used for years and years after that, and I think still in use today. That was a “Bush Hog” brand, which is a pretty tough mower.
There is some risk of tearing the PTO gears out of a tractor, if the pin doesn’t shear (but generally only on little cheap tractors, which yours isn’t) but it’s always a good idea to put some anti-seize on the shaft when you put the shear bolt back in.
As Jem mentioned, use a common grade #2 bolt. Both grade 2 and grade 5 are generally zinc coated and look silver, so the only way you can tell which is which is from the marks on the head (grade 2 will have no marks, grade 5 will have 3 marks). Grade 8 bolts have 6 marks and are usually brass colored.
The brass coloring on grade 8 bolts is actually a zinc coating. It’s a better zinc coating than the silver looking zinc coating on grade 2 and grade 5 bolts.
Sometimes it’s hard to find grade 2 bolts in some hardware stores. In that case I have used tap bolts, which are normally grade 2. I don’t like using tap bolts though, because they are actually a little too weak. Since they are threaded all the way to the head, the average diameter is a little smaller than a regular bolt, hence weaker.
One other thing. If you do ever have to remove the mower blades, on many mowers (if not most) there is a plate you can remove from the top of the mower and you can take the nut off the mower blade from the top side. The swivel bolt which holds the blade on is keyed, so it won’t turn. You do have to get underneath the mower to fit the blade back on, but I generally just prop it up on blocks to do that.
I never sharpen the blades of a bush hog, but I knew one guy who did. He just crawled under it and sharpened the blades with an angle grinder. I abuse my bush hog enough (it’s actually a Woods brand) that if I sharpened the blades, they would stay sharp for about an hour (or less). It makes a terrible racket when I mow all my peach prunings, grinding/throwing chunks of wood against the deck.
They sure can be tough, I had a Landpride I literally mutilated. Bent blades, Bent and dented deck, All the covers had been ripped off. Put new metal on the top for all braces after i dropped it moving it with my grapple, had the gearbox serviced. new blades put on and sold it for 500 bucks. Probably still works today. I dropped some big money on a Woods Brushbull 600XX and it literally cuts 3-4 inch trees down. These things are built serios tough for the right ones…
Your post made me realize I misremembered the brand of my mower. It’s a Landpride (not the Woods I mentioned eariler).
I’ve had some Woods equipment before and very tough. I think Rhino makes some pretty good mowers too.
Thanks for the replies. Yes, I imagine the bolt was just a bit old and maybe rusty, and just popped. At least that’s what I’m hoping that it was. When I go to town I’ll pick me up a bag o’ bolts.
After comments about not needing to sharpen the blades, I may pass on that. But, I do cut mostly pasture grass, briars, and the occasion skinny sapling, so it may benefit to sharpen them. I try to avoid any tree trunks thicker than a couple inches.
I don’t even know what brand it is, it has an old label on it, but it’s faded and mostly tore off. Maybe I could get a pic of it, and someone could perhaps ID it for me.
It’s worth a shot.
One thing I’ll mention. A lot of those old mowers (and old equipment in general) have the pto shields missing, which is very dangerous, imo. Some even have the old square shafts, which is even worse.
Since you are a bit new to equipment, I’ll mention that pto accidents are never mild and generally deadly. I have a friend who knew a guy who got caught in an post hole digger and it sucked him in before he knew what hit him. The scene was so grisly the two other people there when the accident happened, went into shock.
Never hook the pto shaft up (or decouple) while the tractor is running. And don’t go near the PTO shaft while it’s spinning (it’s actually best not to ever get off the tractor while it’s spinning).
If the any pto shields are missing it’s better than a good idea to have them replaced, even if someone slips and falls into a spinning pto, the shield will likely save a life.
I have used a carefully cut piece of PVC pipe as a shield before. While it doesn’t expand/contract like a real pto shield, I put it on a piece of equipment I borrowed, and it was better than nothing.
Pardon, if you already know all of this. In that case, just consider it a good reminder for me.
Thanks, I try to be very careful when I engage my PTO. I usually don’t even get off the tractor until I turn it off, and it’s stopped turning. I’m usually out there by myself, and try not to take any risks while on the tractor. I’m leery about going across and up hills, which we do have a lot of. Some places I don’t even try, not worth it.
Can you elaborate on square shafts? Are you referring to the shape of the pto shaft that slides inside itself? I was told long ago category 1 shafts are the triangular shape and category 2 implements have the heavier walled square tubes. I was told it’s a hp thing. Category 1 ~20-50hp Category 2 ~55-85hp or something close to those numbers.
You’re right. Evidently they still sell all kinds of different shaped shafts. I’m not sure about the horsepower rating, it probably depends on the size/thickness of the square tube. I have seen a lot of old low horsepower equipment with square shafts (which is why I assumed the square shafts were old style).
Here is a chart which shows different shapes of pto shafts. Apparently the shape of the tube depends on the country of origin.
As you know the square shafts were particularly bad about grabbing coats/pants. I have some Cat 2 equipment with the triangle shafts.
Interesting. According to that site, mine is of Italian origin, it is triangular, with those odd points. I’ll try to get a pic of the whole mower soon.
OK, here are some pics of the bush hog, in hopes that someone can figure out what brand it is. Not important, but would be nice to know.
That sticker/paint on the side almost looks like a Bush Hog sticker. From memory, it seems like the Bush Hog brand had stickers with black lettering on a white background. Of course the red color matches the Bush Hog brand.
World Agritech also made rotary cutters which sort of looked like that.
Even if you can’t find the exact make, most of the parts on those mowers are fairly standard, if you measure the right size. There are tons of aftermarket parts, if you need them. Everything from the PTO shafts to the wheel assembly to the gear box, so at least from that perspective you should be good to go.
I had to replace the dishpan/stump jumper on the mower I currently own. That part was only available from the manufacturer.
I would say color is right for Bushhog, but I don’t believe it’s a Bushhog brand. Bushhog (Squealer was the medium duty line) brand usually used a chain from the top link to the tail wheel. They also used a splined pto shaft at the gearbox that needed a shear pin type shaft. The kind that has an “ear” on the shaft toward the tractor side and takes a 5/16 bolt. Bush hog gear boxes were also not interchangeable with almost all other makes. If I remember correctly, the bottom shaft that connects to the blade carrier had a 15 spline shaft where most all others take a 12 spline shaft. Not that is matters much. Be sure your gear box has the proper amount of oil in it (or corn head grease if it has leaky seals).
Thanks for the replies. Quick question, my wife is in town, and I asked her to pick me up some bolts. She went to Tractor Supply and found a bag of supposed shear bolts, about 3" long, 5/16" thick. But, they had 3 lines on top of the bolts, are they grade 5? They were silver colored, zinc I guess?
Those are shear bolts for a pto with “ears” type shear built into the shaft. They are 5/16" and they are grade 5.
Your shear protection is between the pto shaft and the gear box, not on the shaft itself. The bolt you need is a 1/2" grade 2 standard bolt with a Nyloc nut to hold it on. (or you can mash a few threads so a regular nut won’t come off)