Rear Blade Blade not high enough

[Ken45101]

I am curious as to how much the lifting capacity is diminished with the side links attached at that closest hole.

It probably specifies that in the manual, I know mine does. Check in the specifications section where it gives the lift specs.

Ken

 

[MtnViewRanch]

It probably specifies that in the manual, I know mine does. Check in the specifications section where it gives the lift specs.

Ken

Ken, are you telling me to look at the specs? :confused2:

 

[ole farmerbuck]

Anyone know why i'm not getting any email notices about this thread i started? I think i have everything set right. (but then again, i had my 3point set wrong!)

 

[Gordon Gould]

Gordon, thanks so very much for posting theses pictures,:thumbsup: like they say,"a picture is worth a thousand words" Pictures sure help to clarify things.
I have looked at 100's of tractors and have to say that I have never noticed any that had a set of lift holes so close to the pivot point. I am curious as to how much the lifting capacity is diminished with the side links attached at that closest hole.
Anyway, thanks again for putting me straight.

With the side links in the far holes, which are 12" from the pivot point, I have 2870 lbs of lift at the arm lift points. If the side links are in the close holes, which are 6" from the pivot point, I get 1435 lbs of lift at the arm lift points. Still plenty for any blade I could put on my tractor which is in the 30 hp class.

 

[JoeL4330]

FWIW, I have similar problems with my M5040 and a 6' Woods medium duty scraper blade.

It seems to me that the geometry is wrong, as I lift the blade, the bottom tilts more forward. As I drop the blade, the bottom moves to the rear. In effect, the blade is rotating rather than just moving up and down. If I don't have things adjusted just right, the 3pt will go very low with the blade tilted way down in front.

On uneven slightly uneven ground, the blade may hit in the up position...or not touch the ground in the down position. I don't have problems with the box blade.

I suspect that the vertical difference between the top and lower hitch points is a lot shorter than the vertical difference on the tractor end of the 3pt.

I now have a hydraulic top link which helps some but it's still not right.

Ken

The geometry is tricky, but you should be able to correct "angle of attack" of the blade with your hydraulic top link ...if you can't get enough range of motion, consider using a "swinging top link" ...I do, because I also have a hydraulic tail wheel that I can adjust and found that it otherwise fights my top link ...here is a picture of the link I insert between the top link and the implement ...it is the often discussed Harbor Freight link.

These two pics should help explain and show the geometry

 

[Ken45101]

Yes, basically I have to use the hydraulic top link to get decent travel height for the scraper blade.

My rotary cutter has a moving frame for the toplink, so that works well. I ought to look at the mount dimension on the cutter (and box blade) vs. the scraper and see if the scraper has incorrect mount geometry.

I wonder if it has to do with the tractor being cat 1/2 and probably more vertical spacing between the lower arms and the toplink attach point. My scraper blade is supposed to be cat 1/2, but maybe it's not really deigned properly for cat 2?

Ken

 

[MtnViewRanch]

I think that not enough lift for rear blades & landscape rakes is a very common problem. If you think about it, you have the hitch and that whole thing has to be above the rear blade so that it can turn 360*. So the hitch is a bit higher to start with just so that the implement can be adjusted properly. So depending on how one has their 3pt linkage adjusted can make a pretty big difference on how much ground clearance one has with their blade or rake.

 

[Ken45101]

I think that not enough lift for rear blades & landscape rakes is a very common problem. If you think about it, you have the hitch and that whole thing has to be above the rear blade so that it can turn 360*. So the hitch is a bit higher to start with just so that the implement can be adjusted properly. So depending on how one has their 3pt linkage adjusted can make a pretty big difference on how much ground clearance one has with their blade or rake.

OH! I think you may have hit an important point there! Good thinking.:thumbsup:

Ken

 

[ole farmerbuck]

I had my dealer adjust the linkage the other day for the the 3 pt. Seems to make things a lot better.

 

[Baby Grand]

I will do that one next time I am out there. Actually broke the cotter pin on one side, so I have to tinker with it anyhow.

I was amazed how much difference moving the top link had. It is a much more complex setup than you realize at first.

It is a complex as well as an amazingly flexible design, in that you can get all kind of different motions by simply changing the length of a link. Thank you, Harry Ferguson! The 3pt hitch is actually a 4 bar linkage:

Four-bar linkage - Wikipedia, the free encyclopedia

Here's a little animation that you can adjust - a very handy tool for doing some down & dirty design work:

Flash Animation of Four Bar Mechanism

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