MF135 Power Steering

[Cparcher]

This is my first time posting. I have a 73-76-ish MF135 UK version. I rebuilt the Power Steering pump and new steering cylinders as this model has the external
mounted steering cylinders on both front wheels. I rebuilt the system as first the pump oil was leaking into the engine. Now, I have oil at both cylinders and
seems to be pressure but power assist steering still seems rigid and stiff to turn. Like the power steering isn't working at all. I've found many different
versions of the power steering online. However ours has a little shuttle valve mounted on the side of the steering shaft kind of under the battery area. I've
read a few things that talks about a steering cylinder under there as well. But curious if anyone has any ideas. I may have to cut the steering wheel off in
order to get the dash tin off to actually see it in there. It is beyond seized on the shaft.

I'm struggling on how deep I go with this old tractor. It has been in the family since I was a kid so some sentimental value but to be honest every time I turn
around, I need to fix something. Joys of the old girls I guess. Any ideas would be helpful.

On another note, Merry Christmas everyone!.

 

[tractorsam]

The linkage on the side of the steering column relies on a very small amount of vertical play in the steering column. Any lost motion in the linkage could cause the valve not to actuate properly. I think youll have to remove the steering wheel to diagnose the issue.

 

[Stan Coryell]

If the steering cylinders are new, hooked up correctly, and getting 800 psi or more, I'd say that rules out a valve/ hydraulic issue. You might want to look at the front spindles, bushings, bearings, and all the tie rod ends.

Replacing the spindle bushings and getting grease into the rod ends made a noticeable difference in how easy my 202 steered, a very similar tractor.

 

[Dieseltech]

I have the same Grear Britian 135 model. Look closely at the steering valve link ends and pins, when they get worn over time the valve spool does not have the travel needed to turn on the steering assist pressure/flow. That valve MUST move each way for the system to work correctly.