Brush hog top link redux!

[Stihlrunner]

Before flaming commences, I've searched posts about chain top link and understand that is an age old debate. I would like to detail my situation and ask for advice.

I have a Jinma 284 with a 5' King Kutter rotary mower.

The problem I have is I am constantly having to change top link adjustment to keep the front of the mower from digging into the ground, then back to have the tail wheel high enough to not drag. If I back up to mow, then the tail wheel spins around, gouges into the ground and jams up the mower against the rigid top link.

My question is two-fold:

1. Is there a procedure for setting proper tail wheel height?

2. How about a chain top link instead of rigid? Most of my mowing air is flat but hilly, no major ravines but enough dips and whoops to cause the mower deck to dig in. Plus I like to back up to the edge of the bank and mow slightly up it but fear breaking top link off the tractor.

Opinions? Please don't state the well-used verse of the chain link allowing the brush hog to flip up over the operator. I don't even see that as a real possibility, consider the driveline, QA, ROPS, mower lower arms, etc would all prevent it from travelling that far. Has anybody every actually experienced that first hand?

 

[dirt ditch]

I agree that it is imposable for a 3pt mower to hit an object and flip up and smack the operator with the deck. I use a chain for the top link. Here in the sandhills the blades would always be digging in if not for the chain top link. This is the top link I made for the mower. The swivel ball is pinned to the tractor and the chain is pined through the loop in the chain.

View attachment 327287

 

[MtnViewRanch]

How is it that the front of the mower is digging in? Don't you set the height with the 3pt hitch? If the front digs in, you are going through some steeper raveens I would think. I would think that you can adjust the tail wheel so that the height matched the front. Use the chain and you should have it setup so that it follows the contour of the ground.

The ideal setup is to have a hydraulic top link with the float function in the control valve. Put the valve in float mode and you get the maximum flexibility up & down. The mower will follow the ground and you will get a more even cut.

 

[TripleR]

For proper setup, if you don't have the manual, download one from another brand and follow it, it will explain leveling deck, front to back adjustment as well as top link and tail wheel setting. Yes it is possible to set one up properly without using chains, not that there is anything wrong with that, I just don't see it solving your problem.

I agree with MtnViewRanch as to the ideal setup, I just wasn't thinking and didn't get a float valve on mine, so I have to live with it.

 

[jeff9366]

I have a Jinma 284 with a 5' King Kutter rotary mower.

The problem I have is I am constantly having to change top link adjustment to keep the front of the mower from digging into the ground, then back to have the tail wheel high enough to not drag.

Does the Jinma 284 have functioning Position Control? If Jinma has Position Control do you know how to set it?

If tractor does not have Position Control ZERCO CHECK CHAINS are an option. Zercos have been around since the Ford 9N, 60 years, for holding up the front of implements, especially rotary cutters.

Coincidentally, your Jinma has almost the same horsepower and weight as the 1939 Ford 9N, although that has nothing to do with whether the Jinma does/does not have Position Control on the 3-Pt. I always see Jinmas described as "basic", so I am asking, rather than assuming.

Search T-B-N for ZERCO.

There are 16 threads covering check chain/ limit chain situations and hardware.

 

[Stihlrunner]

Thanks for the suggestions, guys! My Jinma doesn't have a float control and the way everything is set up, it doesn't life the the deck extremely high off the ground. Due to this, the tail wheel is never really off the ground, even during transport, unless I crank the top link way up. When I lower the top link to mow, the wheel travels along as normal, however when you reverse it spins around like a shopping cart wheel and changes the height of the deck, usually causing it to scalp the ground. Since the deck doesn't float if you go over a hill the grass doesn't get cut even as on the flats. By hill, I pretty much mean a gentle rise of a few inches.

 

[jeff9366]

Limit Chains are your solution mowing in forward direction. The limit chains control your cut height. I normally cut at 1-1/2", after front of deck is chain-maintained at the height you want, set tail wheel so rear of deck is about 1" higher, ie: 2-1/2" in "normal" operation. Use (right) adjustable lift arm to level cutter deck left-to-right. Chop.

For heavy cutting it is best to push over brush with FEL, then have the cutter chop as it passes over knocked down brush in succession. One pass moving forward.

Your expectations for mowing in reverse may be TOO HIGH. Reverse is more for precision work around trees, boulders, etc.

There is nothing wrong with having some tail wheel ground contact during transport. Ground support under tail wheel markedly reduces strain on the 3-Pt. hitch and implement frame. You won't wear out that laminated rear wheel.

Advise is from my experience. Others may have different opinions based on their equipment and conditions.

 

[TripleR]

Thanks for the suggestions, guys! My Jinma doesn't have a float control and the way everything is set up, it doesn't life the the deck extremely high off the ground. Due to this, the tail wheel is never really off the ground, even during transport, unless I crank the top link way up. When I lower the top link to mow, the wheel travels along as normal, however when you reverse it spins around like a shopping cart wheel and changes the height of the deck, usually causing it to scalp the ground. Since the deck doesn't float if you go over a hill the grass doesn't get cut even as on the flats. By hill, I pretty much mean a gentle rise of a few inches.

So you are saying you don't have a position control 3PH?

 

[Larro Darro]

The rear wheel assembly is designed to lift the mower while backing. If the wheel itself is gouging the grass, check the shaft for wear. And always keep it greased.
I used to use a bush hog at a golf course with the rear wheel removed. We went very slow and cut the roughs with it. On the steep hillsides, it was the only mower we could use. You had to really pay attention to the lift as the land rose and fell.

 

[Stihlrunner]

The rear wheel assembly is designed to lift the mower while backing. If the wheel itself is gouging the grass, check the shaft for wear. And always keep it greased.
I used to use a bush hog at a golf course with the rear wheel removed. We went very slow and cut the roughs with it. On the steep hillsides, it was the only mower we could use. You had to really pay attention to the lift as the land rose and fell.

The shaft is definitely worn. There is a lot of slop both up and down and sideways although it does move freely.

 

[Zebrafive]

Set my mower so the front is slightly lower than the rear. Takes less HP to run.
Since I "rough" cut with mine, I could care less about the tail wheel gouging.
If I am backing just to get a better angle when I go back to forward I will use the 3pt to raise the cutter first.
I am more worried about the tail wheel's wheel bearings when "roading" than wearing out the laminated tire. But at 16mph on the road that's most likely a moot point.

 

[BukitCase]

Good point Jeff, but I believe he was referring to the tail wheel shaft, not the PTO shaft... Steve

 

[8404]

Just cut it out and add a chain, get a hydraulic top link and then you can take out the slack in the chain when you want to lift the tail wheel off the ground or add slack to the chain to let the mower follow the contours of the ground.

 

[Gary Fowler]

I have used chains on my old Yanmar to hold the mower deck at the prescribed height since I could never keep it the same height after raising and lowering but never attached them to a ROPS. I adjusted the chains to the mower height I wanted and then when I dropped the lift down it was always the same height. This prevented the front from skidding on the ground and or being 4" high rather than 2". Tractor Supply sells them complete with chain & attachment brackets for hooking to the 3 ph. One bracket goes on the pin for the lift arms and the other end attached to the tractor where the top link attaches. Most tractors have 2 or 3 holes there and one can be used for the top link and another for the brackets on the chain. The attachment brackets have a slotted hole in one end to adjust the length of the chain. You could also replace the top link with a set of chains for more free floating also when you go thru a ditch. I have seen folks not even attach the top link and just drag the BH on the tail wheels for maximum floating action. I don't like this as you cant raise the tail wheel off the ground.

 

[Larro Darro]

This the small bush hog that came with my B7500. It has chains built into it, between the top link hookup and the frame. It might not work in a bigger mower, but it keeps the back from digging in going over rough ground.

 

[JasG]

The top link on my brush mower pivots. Where I connect my top link on the 3pt is about a 8" part that swings about 180 degrees so the cutter is controlled only by the lower links and the tail wheel. It came that way from the factory. I've seen several finish mowers set up similar. I've used ones with ridged top links and it is a pain when doing rolling ground.

 

[herringchoker]

My cutter came from the factory with a chain as the link between the TPH toplink and the rear of the deck. Since my tractor does not have position control, I installed the Poor Man's Position Control (PMPC) to set the front height to avoid gouging and maintain a consistent cut. Works like a charm. The PMPC came from my scrap pile...as TBNer Renze says "free scrap is a good investment".

 

[Stihlrunner]

After reading all the input I think I've been asking too much of the hog to expect it to cut well at varying height levels. Pretty much I need to decide on the height I'm happy at and optimize it for that.

I set the tail wheel height to KK instructions. I plan on mowing tonight so we'll see if that helps. Another thing I think that fouls up my game is the HF quick hitch which kind of screws up my adjustability and puts the mower deck farther away from the tractor.

If I don't get satisfaction with these adjustments I'm going to try the chain top link. Thanks for all the input, as always I learn a bunch from this forum.