Case IH 4890 4894 Steering Modification

[79vwrabbit]

About 18 months ago the force motor (part number A47512) for the rear steering failed on our Case 4894 tractor. We were unable to get a replacement part (not even a salvage part of any kind), and so we had to take matters into our own hands.

After a lot of trial-and-error, we settled on a modification that works very well. Basically, we converted to 100% hydraulic steering and removed or disconnected all electronic steering parts.

The complete explanation is here:
https://www.youtube.com/watch?v=064WwsfRNtQ

And here is a short demo:
https://www.youtube.com/watch?v=CKhXeDeN4Mw

 

[rndy3788]

(quoted from post at 23:44:56 08/24/21) About 18 months ago the force motor (part number A47512) for the rear steering failed on our Case 4894 tractor. We were unable to get a replacement part (not even a salvage part of any kind), and so we had to take matters into our own hands.

After a lot of trial-and-error, we settled on a modification that works very well. Basically, we converted to 100% hydraulic steering and removed or disconnected all electronic steering parts.

The complete explanation is here:
https://www.youtube.com/watch?v=064WwsfRNtQ

And here is a short demo:
https://www.youtube.com/watch?v=CKhXeDeN4Mw

wesome idea , last fall i unhooked the rear steering and hooked it up to a unused hydraulic remote valve mostly just use the front steering and only turning around on ends i need to use remote for rear at least this way it doesnt drift but I really like your system thanks

 

[John Saeli]

Very interesting. I don't understand how the smaller front cyl's act as masters and the larger rear cyl's are the slaves. Maybe I missed it,
but is the result that the rears don't turn as sharp as the fronts?

 

[4435]

Thanks, something to keep in my tool box. Tom

 

[79vwrabbit]

(quoted from post at 17:30:45 08/24/21) Very interesting. I don't understand how the smaller front cyl's act as masters and the larger rear cyl's are the slaves. Maybe I missed it,
but is the result that the rears don't turn as sharp as the fronts?

You're likely correct that there is some difference in turning because of the differences in the cylinders.
In practice, we haven't noticed any difference - the steering behaves very similar to how it was before modification (before the force motor died). We never measured turning angles before & after so we honestly don't know for sure.