New guy here...Some brushhog questions

[ericinok]

I have recently purchased a Kubota L3010 to keep up my 20 acres that I bought last year. I had an old '53 Ford Jubilee that I tried to use to brushhog, but it died quickly. The 5' Ag-King cutter is still in fairly good condition, so I hooked it up this weekend to the Orange Machine and started cutting.

After getting hooked up, I noticed the link arms (lift arms, whatever you call the 2 arms on either side and below the PTO) will actually rub the tires when turning or on a slope. This can't be good for the tires, the mower or me. From the wear patterns on the tires, it appears the previous owner experienced this also, because the inside of the treads are a little worn where the arms are positioned. I checked out the Jubilee, and it had the PTO and arms that stuck out much further behind the tractor, whereas the Kubota has all it's junk right below the seat. Any idea on this one? I thought of extending the arms out further, but I'm not sure I'm comfortable extending out the jackshaft more than it is right now (which is much more than when on the Ford).

Speaking of the jackshaft - when I engaged the PTO, the bolt that holds the jackshaft to the brushhog immediately snapped. I then put another bolt in, and it did it again. Mind you, I had the engine at a pretty low RPM both times. I then went to the hardware store and bought the strongest bolts and nuts they had and put one on there. It worked until I started it back up again after lunch. I guess the morale to my story is "never stop for lunch". I know that's a lot of resistance when the PTO is engaged, but it doesn't seem like it should be snapping bolts like that. I had the deck raised and the RPM's low, like I said. Could there be something on the cutter that needs work? It's pretty old, and probably needs a little love.

There are my first two issues. I appreciate any help I can get. You are welcome to make fun of my lack of knowledge, and call me any name you wish, as long as you also give me a good solution.

 

[beersngars]

Hi there, I know exacly what you mean about the lower arm to tire clearence. I just had my new L3400HST delivered yesterday and on mine there are stabilizer bars with turn buckles on the outside if the lower arms. I asked the salesman and he said they were a good idea with some implements but not necesary on others. My quess is most of the smaller tractors will need some type of brace as most are narrow.

As to the bolts breaking, there must be something binding or seized. Better figure it out as stonger bolts aren't the answer.

 

[atgreene]

The lift arms should have a turn buckle or pin type arm stay that prevents either arm from moving too far near the tires as well as prevent the implement from swinging back and forth. With a rotary mower, this is important on a hillside.

There should be a large hole in the lift arm and a place under the axle of the tractor for this turnbuckle to attach.

As far as your bolt in the pto shaft (the shaft is called a power take off shaft) it should be a grade 3 or 5 and is designed to break if you encounter an immovable object (rock, stump etc...) and prevent the pto shaft or gear box from disinigrating. Do you have a two stage clutch? If you step on the clutch partway, does the tractor stop moving but the pto continue? I'm not familair with Kubota 3010, but if this is out of adjustment I suppose you could be snapping the pto shaft. Do you also have a slip clutch? If not, you can buy a slide-on slip clutch that will go on your pto shaft on the rear of the tractor.

How are you engaging the pto, do you ease out on the clutch or just throw the lever to engage it? A quick jerk can, but shouldn't, snap the shear pin/bolt. Can you turn the pto by hand and have the rotary mower blades turn? You should be able to free-spin the shaft and make the blades turn, if not, your gearbox on the rotary may be bound. Check the fluid in the gearbox while you're at it, just to be safe. The gearbox lower seal just above the blades is notorious for leaking and the box then runs without oil, very bad.

Here's a link on one place you can buy a slip clutch, they are available at most tractor supply places and maybe even here at one of the links.
PTO Slip Clutch

 

[travis potter]

I can't help on the arms but on the bolt my understanding is it should be a soft bolt to protect the PTO in the tractor if it is a hard bolt and you hit something it will not break and ruin the pto. Try turning the gearbox by hand it should turn freeley with only the weight of the blades causing resistance if not you could have picked up some wire under the bh (last week for me) If the lower seal is leaking {mine} fill the gear box with heavy grease [several years for me]. Hope this helps.

 

[ericinok]

I was able to turn the pto and make the blades turn by hand, so I don't believe that anything is unmovable. Once I put the big bolt in, I was able to enagage it and actually got about 5 acres mowed before lunch.

Then, when I started it up again is when the bolt came out. It did not break like the smaller ones, it just bent and the nut came lose.

My L3010 has a HST. I just engaged the pto at a slow rpm with the deck raised. I eased it over, so it would not start rapidly, but it still would break the bolt right away. I'm wondering now if I should maybe push in the clutch and have it start up even slower. The tractor did not come with an owners manual, the dealer is supposed to have me one this week.

Sounds like a stronger bolt is not the answer. I'll oil up the gearbox on the mower and try the clutch. Thanks.

 

[IslandTractor]

You say you are new so I will ask...are you sure it is the right size bolt? The bolt should fill the shear bolt hole completely. 1/2 inch is usually what a 4 or 5 ft cutter would use.

We've all broken shear bolts but your initial experiences were odd in that you were breaking so many. The last time you say the bolt was bent....that is real hard to do if it is the right size as there is no room for it to bend. It breaks rather than bends. Maybe it bent as it was coming out as you mentioned that the bolt had fallen off. (use a lock washer by the way)

 

[Grrrr]

One other thing about the bolts...

Have you tried buying any bolts labelled as shear bolts. The last time I wanted some there were about ten different hardnesses in the shop and I wasn't sure which one was best. I ended up with a medium hardness one as that is what the guy suggested.

I don't think normal bolts are quite the same as shear bolts.

 

[jbrumberg]

ericinok:

No one should laugh at you here at TBN. We all have had our "learning curves"; some more accelerated than others ! All of the previous posters offer good suggestions. I would look at the lower seal for leakage and see if wire and/or bailing string is binding up the lower shaft. You did not mention any problems with vibration, but make sure that the cutting blades are clear of debris and free swinging on the blade pan/stump jumper plate. I would also check the blades for cracks, knicks, and gouges. It does not take a lot of missing metal to throw a rotary cutter out of balance. Just some additional hints regarding rotary cutter use. Jay

 

[excel25]

on my 3010HST I have to use the clutch and let it out slow Works great!!

 

[MarkV]

As far as tire clearance goes. Can the pins be remounted to point to the inside of the bush hog frame? I did that for a small tractor that did not have enough spread on the lift arms. The tires on that tractor can be set for a wider stance and may be at their narrowest setting now.

MarkV