found a good use for the top hole on the 3pt topln

[Soundguy]

I've seen alot of discussion on not using the top hole on the toplink connection on the N tractors, like my 8N.. seems the torque is too high, and can rip the guts out of the draft controlls, etc.

Most people I know use that hole to store an extra toplink pin.... as a reminder not to use it.

I cobbled up a hazard plaqard that the bracket uses that hole.. but doesn't interfere with the other two, or hit the driver in the seat...
this way, there is no way to accidentally forget and us ethe top hole... or if you loan the tractor out ( gasp!/w3tcompact/icons/eyes.gif ) it won't accidentally happen either.

Soundguy

 

[beenthere]

<font color=blue>""can rip the guts out of the draft controlls, etc.""<font color=black>

Hmmmm? I thought I'd been around 8N Fords enough that I knew a bit about them, but I have never heard anything about not using the "top hole". Any resources that discuss this problem that you can point us to? I would like to learn more about the problem, and what type of force "rips the guts out of the draft controls, etc."

Thanks for the heads up on this.

 

[Anonymous Poster]

I think what Sound is referring to is the undue force that the top link exerts in a forward direction on the spring and the mechanism which operates the draft control. Apparently there is a limit to how much total bottomed-out pressure that valve can stand before it breaks....mechanically not hydraulically. As you know, the plow point is the end of the lever and the lower links are the pivot which puts the compression force on the top link which is Harry Ferguson's basic idea. There apparently is a limit to how much it will take. You can demonstrate the action on some three point tractors by lifting the top link straight up and pulling forward on the up end of it and watch the lower links pop up as the internal valve opens.

 

[bgott]

The three holes in the top link rocker are for heavy, medium and light draft, starting at the bottom. I've read that the only practical usage, as far as the draft control is concerned, for the top hole is when pulling a cultivator in loose sand. The owners manual states that using the top hole while pulling a heavy draft implement will drive the draft control hydraulics buggy. Not in those words, of course. One of the best investments I made when I bought my 8N was a reprint of the owners manual. I got a reprint of the parts manual, too. I believe Don at just8ns.com has them.

 

[Soundguy]

<A target="_blank" HREF=http://www.ytmag.com/nboard/wwwboard1.html>http://www.ytmag.com/nboard/wwwboard1.html</A>

I also read about tractors on the above club.. it is for 8n, 9n, and 2n tractors.

And yeas, as others have said, the forces applied to the toplink top hole can be pretty high, considering the 3pt system is a lever, etc.

Soundguy

 

[beenthere]

That is a good explanation, and I can see (if using a ground engaging attachment) that the top hole could work the draft control a lot, causing erratic draft (depth) control. Thanks for the clear description.