MF 20C industrial Power Steering issue

[etmountianman71]

I am throwing something out there and would like some thoughts from the masses. Finally got a second tractor to help out with on the farm- mainly for hay season.
I have a Massey Ferguson 20C Industrial tractor (almost like a 245) with a power steering issue. It will not steer to the left unless you are at a high rev and you continually turn the steering wheel while driving. Makes it interesting to drive down the road to hay fields or backing up to equipment. You can manage while driving in the field but you are always turning the wheel to keep straight as the tractor wants to just wants to follow the contour of the land. (guess i will put a spinner on it ).
While stationary the tractor will turn to the right with no issues but not to the left (steering wheel will just rotate).
While driving the tractor will turn to the right with no issues but you have to continually spin the wheel to go left.
I have completed the following:
1. Rebuilt the two cylinders on the front to each wheel. (taking time to make sure that I put them back together exactly like they came apart)
2. Replaced the total of 4 hoses (two per cylinder) on the front end.
3. Then had to have the Hydrostatic pump assembly (under the steering wheel) rebuilt as the shaft and bushings were bad and started leaking.
4. Replaced steering wheel as it was bad (previous owner had placed a metal wedge in around the shaft- nice)
5. Replaced the Power Steering pump with a new one.
6. No leaks are visible.
7. Each time i have bleed the system at different locations.

*I have two thoughts left to as what the problem might still be.
1. Air captured in the metal lines where they bend.
2. The two cylinders, one or both of them are not working as should even though they have new seals and orings.

 

[rla442]

I'd try to swap out the right and left cylinders on the front axle to narrow it down and try eliminate the cylinders. Then you can start chasing lines if its not the cylinders.

 

[etmountianman71]

Thanks for the reply.
Still triaging the ordeal.

 

[918bones]

Hi I have the same tractor that I am currently restoring. Its been a fun project so far....not.. I have repaired everything leaking on this Messy Ferguson but I am having the exact same problem as you are having! I have tried to bleed it several times at the cylinders to no avail. When the wheels are off the ground it works perfect. As soon as the front wheels are back on the ground and under a load it works one time to the left then the steering wheel spins. If I spin it fast it catches and eventually turn left. The right it works perfect. Did you find out what was causing your issue? The next thing I am going to try is to pull the hood and battery box to try bleeding the pump assembly because the highest power steering line is the return for the left cylinder. I will report back if that solves the problem. If you solved your problem can you let me know what you did?
Thanks!
Al

 

[etmountianman71]

Well I no longer have the tractor as i am trying to move up to a four wheel drive.
But the fix: I had to rebuild the two steering cylinders on the front wheels a second time, this time made sure that all (key note) orings and seals were replaced. Then it made it about 98% better. So combining all the previous work made a difference but the final rebuild of the front cylinders topped it off. The bleed thru of fluid was enough to allow no pressure build up. It made it where you could actually drive the tractor and work.