Explain Draft On Tractors
Printed From: Unofficial Allis
Category: Allis Chalmers
Forum Name: Farm Equipment
Forum Description: everything about Allis-Chalmers farm equipment
URL: https://www.allischalmers.com/forum/forum_posts.asp?TID=54893
Printed Date: 10 Sep 2025 at 3:37pm
Software Version: Web Wiz Forums 11.10 - http://www.webwizforums.com
Topic: Explain Draft On Tractors
Posted By: PlayGun
Subject: Explain Draft On Tractors
Date Posted: 07 Aug 2012 at 2:16pm
Can someone give a good explanation of how the draft features work on tractors, and how to set them. haven't ran one in 20 years since I was a boy and just don't remember. I gather that the AC tractors have a different system than others.
-------------
Hopefully Future AC Man! Ride With Jesus my friends! Lonas
|
Replies:
Posted By: CTuckerNWIL
Date Posted: 07 Aug 2012 at 3:51pm
The 8N Ford has a connection to the top link bracket that is spring loaded and the heavier the pull the more you compress the spring. The other end is connected to a valve that passes hydraulic pressure to the lift arms when the system is in draft control instead of position control.
-------------
http://www.ae-ta.com" rel="nofollow - http://www.ae-ta.com
Lena 1935 WC12xxx, Willie 1951 CA6xx Dad bought new, 1954WD45 PS, 1960 D17 NF
|
Posted By: Orange Blood
Date Posted: 07 Aug 2012 at 5:12pm
Basically in a nutshell, engineers know that pulling harder equals more tire slip, and less productivity. So when you set the draft, you tell the tractor via linkages that if the pull force increases, lift the implement ever so slightly to put more weight on the rear tires, thus reducing slip. Typically lifting the implement a very small amount will not reduce the implements effectiveness at doing whatever it is designed to do. The reason this is automatic rather than just caring the weight on the tractor all the time, is to compensate for varying ground conditions, hills, and other things like compaction from the rear tires. Every manufacture does it differently if they do it at all. As Charlie described the way Ford used to do it, Allis did it with the lower drawbar connection, and on later tractors the point at which the lower 3-point arms connect to the differential case.
-------------
Still in use:
HD7 WC C CA WD 2-WD45 WD45LP WD45D D14 3-D17 D17LP 2-D19D D19LP 190XTD 190XTLP 720 D21 220 7020 7030 7040 7045 3-7060
Projects: 3-U UC 2-G 2-B 2-C CA 7-WC RC WDLP WF D14 D21 210 7045 N7
|
|