3-Point Hitch Need advice on top link height with finishing mower

[CausticUrbanCoast]

You realize that all you have to do for it to flop down is go over the crest of a hill right? It doesn't just stay there in all conditions, or even most conditions. Raise the implement and put it down it will fall down.

The difference is above and behind the pivot, at that point it can not fall down. If it is ahead and lower of the pivot the mower also cannot be lifted as there is no leverage, at best you can tilt the back up.

 

[Russ5160]

I’ve been around tractors for a good while but this is really confusing to me. I must be missing something. I purchased a 7 foot finishing mower for my tractor and the top link is too high on my tractor or the floating top link on the mower is too low. I purchased an 18 inch top link at HF just to see if that would fix the problem because mine was too long. Now the top link bangs up against the driveshaft which will not work. See photos and any advice will be appreciated.
View attachment 710661View attachment 710662

Remove bolt and the green attachment and extend the top link to reach where the bolt was and run pin thru it

 

[sea2summit]

The difference is above and behind the pivot, at that point it can not fall down. If it is ahead and lower of the pivot the mower also cannot be lifted as there is no leverage, at best you can tilt the back up.

The bottom arms are set so when you go over a hill/bump the front of the tractor drops and the rear of the mower is lower than the front of the mower. This would cause the toplink to go "taunt" and/or lift the rear of the mower. When it comes back down gravity will pull the toplink down and the pivot will be below the attachment point.

I don't know what you mean by tilt the back up. Lifting the bottom arms will lift the front of the mower until the toplink takes a load to lift the mower, if it can at that adjustment.

I've got to go look at the manual but I'm pretty sure my BrushHog finish mower said it should adjusted to sag 2" below the pin on the mower. That's the way I've always done it anyway, lets the mower float as needed but doesn't take too much to lift the mower as needed.

I think in the OP's case the tractor frame may be too large for the mower (cat 2?) so the geometry is messed up for him.

 

[Snowflakes]

I would use a shorter top link. It will pick up the slack and be more away from the driveshaft.

 

[CausticUrbanCoast]

The bottom arms are set so when you go over a hill/bump the front of the tractor drops and the rear of the mower is lower than the front of the mower. This would cause the toplink to go "taunt" and/or lift the rear of the mower. When it comes back down gravity will pull the toplink down and the pivot will be below the attachment point.

I don't know what you mean by tilt the back up. Lifting the bottom arms will lift the front of the mower until the toplink takes a load to lift the mower, if it can at that adjustment.

I've got to go look at the manual but I'm pretty sure my BrushHog finish mower said it should adjusted to sag 2" below the pin on the mower. That's the way I've always done it anyway, lets the mower float as needed but doesn't take too much to lift the mower as needed.

I think in the OP's case the tractor frame may be too large for the mower (cat 2?) so the geometry is messed up for him.

The same thing. Your middle paragraph is the problem being addressed.

 

[CADplans]

The same thing. Your middle paragraph is the problem being addressed.

The back of the mower must be able to travel up and down in relation to the front of the mower.
If the top link is too short, as the rear drops to follow the terrain, the top link becomes tight, and lifts the rear wheels off the lawn.

It was mentioned that you could run with no top link.
Without a top link, you can never lift the rear of the mower.
How do you go over a stump, rock, or other obstacle? Mow around it?
How do you travel down the paved road to mow your daughters lawn 1/4 mile away, if the wheels of the back of the mower are touching? What, travel 5MPH so you do not destroy the gauge wheels??
How would you cross a ditch ??
You need the capability to lift the mower, unless,, again,, you are on a pool table.

There are other answers, like the kit that will adapt the mower to a quick hitch,,
but, those answers cost $$$.

Here is another pic of a different Woods mower that I have owned,
the same answer for that part.

A simple cut of the swiveling part, and drilling the new holes costs almost nothing.

 

[CausticUrbanCoast]

The back of the mower must be able to travel up and down in relation to the front of the mower.
If the top link is too short, as the rear drops to follow the terrain, the top link becomes tight, and lifts the rear wheels off the lawn.

It was mentioned that you could run with no top link.
Without a top link, you can never lift the rear of the mower.
How do you go over a stump, rock, or other obstacle? Mow around it?
How do you travel down the paved road to mow your daughters lawn 1/4 mile away, if the wheels of the back of the mower are touching? What, travel 5MPH so you do not destroy the gauge wheels??
How would you cross a ditch ??
You need the capability to lift the mower, unless,, again,, you are on a pool table.

There are other answers, like the kit that will adapt the mower to a quick hitch,,
but, those answers cost $$$.

Here is another pic of a different Woods mower that I have owned,
the same answer for that part.View attachment 710715

A simple cut of the swiveling part, and drilling the new holes costs almost nothing.

... not overly following what you are addressing.

 

[LittleBill21]

pretty sure you just have to move these 2 bolts down to adjust the angle, i see 0 reason to modify a brand new machine

https://imgur.com/TkpzFQl

 

[JWR]

I’ll check my draft control as well, thank you.

Nah, this is not a Draft control issue. (IMO of course.)

 

[JWR]

Thank you again for your help and the photos! I’m trying that in the morning.

No, that arrangement for the flex mower/clevis style end of the top link is not good. If you look at his picture (home welding, black metal) that leaves very little leeway for the mower to go up when crossing ditches, etc. and could/will try to shove the top link forward tending to suspend the whole tractor/mower rig in the air above the ditch (!) It won't but it will do damage trying.

 

[CausticUrbanCoast]

Here is the setup page from the manual for the frontier mower, in the rear mount configuration the floating toplink goes above the apex of the three point triangle.

Inside the triangle is for the front mount so it can tilt up.

 

[CausticUrbanCoast]

No, that arrangement for the felx mower end of the top link is not good. If you look at his picture (home welding, black metal) that leaves very little leewauy for the mower to go up when crossing ditches, etc. and could/will try to shove the top link forward tending to suspend the whole tractor/mower rig in the air above the ditch (!) It won't but it will do damage trying.

Home welding? That is a BE Agri heavy brush mower.

 

[JWR]

My old 6 ft finish mower has chains and a fixed top link pin to the implement has worked great for 15 yrs,

You are getting warm. My comments are:
1) The OP's top link position (as another guy said) is wierd. Not sure what the issue (odd tractor ? Not SAE std 3pt dimensions? ) is but you need to use a lower hole for the top link attach point on the tractor. A previous post said that made it worse. It won't after the rest of the problem is fixed. I could be fooled by the pictures but pay attention to this: Your goal should be to have the top link closer to the same angle relative to the ground as your PTO drive shaft when in normal flat mowing position. (That's regardless of which top link attach hole you use.) Don't have to match but needs to be closer. From side view it ought to look like a parallelogram moving up and down.
2) When I say 3gunr is getting warm, I too run chains on a bush hog from the A-frame back to the rear of the hog. However, looking at this finish mower I think you want to retain the stiff structure above the deck of the mower. To do that just use a single chain between top of the fixed A-frame (getting rid of the original swinging clevis) and the tractor top link attach point, getting rid of the stiff top link. The combo of using chain there and choosing the top link attach point solves your problems. The chain allows all the freedom you need for the mower to go high crossing a ditch, etc. As you said you DO have to be careful not to put the PTO shaft/u-joint at too bad of an angle but you, as operator, should/can control that. Don't expect the hitch-up configuration to always prevent it. Choosing the top link attach point for best angles on the tractor [closer to parallel with the drive line] also reduces the variation in U-joint angle as you raise and lower the mower.

The chain length replacing the top link becomes your adjustment for the comproimise between allowing adequate up down motion of the rear of the mower crossing ditches and humps versus being able to pick up the mower as desired.

I think you will be AOK with my suggested configuration above.

 

[MUDONTHETIRES]

Okay, I may be on to something. Sorry for the back and forth. I purchased a Frontier GM2084R. After checking it out more, I found a sticker from the dealer on my top hitch support which states GM2072 which you’ll see in my photos. It’s also #1 in pdf photo. The top hitch arms (#2 in pdf) are also longer on the GM2084 than on the GM2072. Then I observed the lower hitch arms. I have the GM2072 hitch arms as opposed to the GM2084 that I should have which is also denoted in the photos. I called the service department and was told the top hitch support for the GM2084 is taller than the GM2072 and costs more. So……I think I purchased a new 7 ft mower with a 6 ft mower front end. Could this be my problem? Maybe my mower is too close because of shorter lower hitch arms and too low because of shorter top hitch support?

 

[Midniteoyl]

View attachment 710662

Have some bar stock that you could use to raise that mounting point?

Don't know how old this mower is, but.. I'm back to my original suggestion of extending that flex hinge's mounting point to be about 3" higher.

ie: That point at 19" in your 2nd pic, move it up about 3" using bar stock. Bolt and weld the new bar stock to the uprights using a pipe as a spacer to maintain the separation. Then shorten the flex hitch by about and inch ('cause it really is too long) and mount it using the raised point.

 

[bilneif]

I do but it pushed the floating link down more into the driveshaft.

I have a very similar setup. JD 870, Frontier 6 ft finish mower. If i remember correctly, The manual say that the top link should be lined up with the pins on lift arms. If that]s the case, your top link needs to be much shorter. The top link on my setup is almost parallel to the ground. Has worked great for the past 4 years.

 

[sea2summit]

Okay, I may be on to something. Sorry for the back and forth. I purchased a Frontier GM2084R. After checking it out more, I found a sticker from the dealer on my top hitch support which states GM2072 which you’ll see in my photos. It’s also #1 in pdf photo. The top hitch arms (#2 in pdf) are also longer on the GM2084 than on the GM2072. Then I observed the lower hitch arms. I have the GM2072 hitch arms as opposed to the GM2084 that I should have which is also denoted in the photos. I called the service department and was told the top hitch support for the GM2084 is taller than the GM2072 and costs more. So……I think I purchased a new 7 ft mower with a 6 ft mower front end. Could this be my problem? Maybe my mower is too close because of shorter lower hitch arms and too low because of shorter top hitch support?
View attachment 710728View attachment 710729View attachment 710730View attachment 710731

If true that could be a big part of the problem.

 

[NCL4701]

I had a similar problem with about 10 acres, approximately 1/4 acre of which is sort of flat and the rest cut up and rough. JWR’s and other’s chain suggestion is probably the most cost effective solution. I went with a hydraulic top link hooked to a rear remote with float function. I can, and do, flip it up to cross the creeks or load it on the trailer, put it in float when mowing to follow ground contour, take it out of float to raise over obstacles, all very quickly without leaving the seat or stopping. I’m aware that’s not a cheap solution but it’s a really sweet setup.

It’s also very nice for grading work to have hydraulic top and side link so it’s not strictly for mowing. At times, floating the side link is better for some grading operations which can be done by swapping the remote connections.

 

[JWR]

Okay, I may be on to something. Sorry for the back and forth. I purchased a Frontier GM2084R. After checking it out more, I found a sticker from the dealer on my top hitch support which states GM2072 which you’ll see in my photos. It’s also #1 in pdf photo. The top hitch arms (#2 in pdf) are also longer on the GM2084 than on the GM2072. Then I observed the lower hitch arms. I have the GM2072 hitch arms as opposed to the GM2084 that I should have which is also denoted in the photos. I called the service department and was told the top hitch support for the GM2084 is taller than the GM2072 and costs more. So……I think I purchased a new 7 ft mower with a 6 ft mower front end. Could this be my problem? Maybe my mower is too close because of shorter lower hitch arms and too low because of shorter top hitch support?
View attachment 710728View attachment 710729View attachment 710730View attachment 710731

Well that is NEW light on things. If this is a new machine and you got the wrong mounting hardware on it (which it sure looks like you did) then DO NOT modify or dick with anything ! Insist that the dealer set it up right. Even if he wants a few bucks more to do that, you are way better off than modifying a brand new attachment !

 

[Midniteoyl]

edit: For the record, my post suggesting a modification was posting at the same time as his new revelation.

So, in that light:

That makes sense. We all knew that something was funky with that setup, and it looks like you found out why. Agreed with making the *dealer* make this right. He shouldn't charge you for it either (unless you made the mistake, of course). Insist on a correction.