setting top link on 1735m and a Brush Hog

pattycake · Jul 17, 2020

Can someone tell me how to setup/adjust the top link for a 1735m and a 6' Brush Hog (yep, that's the name brand).

I visited a YouTube video that said that the top link should be attached to the bottom hole on the tractor (there are 4 holes), that the top holes are for a box blade or a tiller.

And.... that the process was, disconnect the top link.... then adjust the height using the bottom links so that the front of the brush hog is about an inch off the ground, the back being about 2 inches (for grass blowout). Once the bottom links are set, then install the top link and "snug it kinda tight".

Please tell me how you adjust yours (or how it should be done).

-thx-

Roadworthy · Jul 17, 2020

Silly me, I usually use the top hole. I suggest using the hole that puts you most easily into the desired range of adjustment. Adjusting the bottom links is done hydraulically with the three point control. You raise them until the desired height is achieved. The top link can then be installed and adjusted to a length to take up the distance between the chosen mount hole and the mower. Once adjusted to that length there is a lock nut to tighten to prevent it from changing its adjustment due to vibration.

JWR · Jul 18, 2020

The Bush Hog brand is top rung. Good machines. What tractor you are using doesn't matter as top link adjustment is the same. I see very little difference which attachment hole you use for the top link when using a Bush Hog. Just try the extremes (highest, lowest) and see if it matters for you. Now about the top link length/adjustment: It is always a compromise between being tight enough (so that you can pick it up as high as you want to) and being loose enough (so that the hog can "droop down over a hump or rise that you go over." ) That's really the crux of the compromise on top link setting. I always put in a plug for an hydraulic top link because that lets you set the thing to suit yourself during operations. It is expense of course to tie up a remote, to buy the hyd top link, etc. but I love mine (on a larger tractor.) The other 3rd leg of a compromise is "how deep a gulley can you traverse tolerating the hog folding up high behind the tractor." There's a whole other debate about that but I prefer replacing the factory hog linkage (yours are steel straps with a folding clevis to allow folding I am sure) with chain. To me chain is the universal solution with no drawback. All that said, if you use a chain then there are only 2 legs to the compromise: The 2 I bolded above.

Note that the You Tube advice fails to allow for letting the droop of the hog over undulating humps and rises -- if "snug" on the level the hog will always be rising off the ground at times when you cross a hump and do not want it lifted off the ground.

pattycake · Jul 19, 2020

Great advice - I never even thought about the issue of dropping down in a gully. No gullys here but plenty of hills so, thank you for the sage advice.

I was going to try and mow at the drop-offs at my pond by backing the mower down the bank but now I see where that won't be possible - the top link will prevent the mower from dropping down the bank. Bummer

LRover · Jul 19, 2020

With my 1635, I usually use the bottom hole for the top link. I raise the mower to my desired cutting height and then lengthen or shorten the top link until the mower is level. My mower gives me the best cut when I adjust it this way.

JWR · Jul 19, 2020

LRover said:
With my 1635, I usually use the bottom hole for the top link. I raise the mower to my desired cutting height and then lengthen or shorten the top link until the mower is level. My mower gives me the best cut when I adjust it this way. View attachment 663767

LRover I respectfully disagree. Everyone helps everyone else when they provide an accurate report from their experience -- and I'm sure you did exactly that. However: 1) When you raise the mower to desired cutting height and then adjust the top link to level the deck that statement inherently means you have taken all the slack out of the top linkage. That means there is zero ability to "droop" the deck allowing it to fold down over humps that you go over (specifically over the pond bank this owner is mentioning planning to back down over.) 2) Nearly all the recommendations I've seen including those from the Bush Hog manuals say to raise the rear of the mower somewhat above the front edge in your final mowing configuration, held there by the back wheel of course, not the top link, and NOT level with the front. And 3) Using the bottom hole is fine, I just don't think it matters.

And I am puzzled by your photo because it seems to show you are not cutting much off the grass you are going over. Is that intended? Seems strange the grass is still that high where you have mowed.

kthompson · Jul 19, 2020

As to which hole to use for the 3rd arm, look at your tractor manual. Some tractors will say use the bottom hole or the top hole compared and it has to do with the design of their 3rd arm mount. Especially on a tractor with draft control.

3gunr · Jul 19, 2020

If you are mowing a nice flat field ,You can take the top link off altogether, The cutter will lust ride over the ground evenly . You just cant lift it up all the wayif you have to go over something. But i agree that chains are the way to go.

LRover · Jul 19, 2020

JWR said:
LRover I respectfully disagree. Everyone helps everyone else when they provide an accurate report from their experience -- and I'm sure you did exactly that. However: 1) When you raise the mower to desired cutting height and then adjust the top link to level the deck that statement inherently means you have taken all the slack out of the top linkage. That means there is zero ability to "droop" the deck allowing it to fold down over humps that you go over (specifically over the pond bank this owner is mentioning planning to back down over.) 2) Nearly all the recommendations I've seen including those from the Bush Hog manuals say to raise the rear of the mower somewhat above the front edge in your final mowing configuration, held there by the back wheel of course, not the top link, and NOT level with the front. And 3) Using the bottom hole is fine, I just don't think it matters.

And I am puzzled by your photo because it seems to show you are not cutting much off the grass you are going over. Is that intended? Seems strange the grass is still that high where you have mowed.

I do have a little slack in the top link though it may not be very obvious. You can see in the photo that the mower's top hitch is not completely straight indicating some top link slack. The design of the mower's top hitch does allow for float similar to a chain. I have it set with the gauge wheel contacting the ground and I should have mentioned that I adjusted that in my first reply. No need for much "drooping" in this field of mine as this is a fairly level pasture but I do understand the OP's need to be able to mow around his pond. The intent of my post was to show an initial mower adjustment in a level field with a tractor similar to his. My 6' Woods brand mower works best for me level. My 5' King Kutter brand mower is a rear discharge and having the mower adjusted with the back raised slightly higher that the front does help with the discharge pattern of cut grass when it's heavy.

In the photo the mower was set to leave about 8-10 inches of grass as I graze this pasture and I turned stock in it after it was mowed. The grass was waist high in spots this spring and that was one reason I bothered to get off the tractor to take the picture. Here is another photo that might show better how tall the grass was.