mf 20 power steering not working

[mdkelley]

I ordered the MF20 service manual from this website yesterday but not sure when it will get here...

I bought a MF20 with MF32 loader and rear 3pt/PTO yesterday. The seller claimed the steering worked fine when he got the tractor (of course) but it just quit and he hasn't owned the tractor long, I would guess maybe a year or so. Everything else seems to work fine, going out to adjust the brakes after I post this.

I am trying to figure out where the power steering filter may be on this model. It has the round steering pump on the right side (opposite side as the lift pump), not the kidney shaped unit I see on the agco parts diagram that has an internal filter. The unit is full of fluid, looks to be just red ATF. Since the pump appears to be full with fluid, I figure the next step is to replace the filter to see if that is causing the steering not to work. I am hoping the service manual will show this type of pump. I don't see any major leaks and would think the fluid would be low if there were a leak.

serial 9A I759I2 (guessing the I's are the stamp that was used for a 1, but it is definitely an I)

 

[MKinON]

The filter is inside the canister. Take out the machine screws around the leading edge and pull the canister back. Have
something to catch the oil and be careful of the large o-ring that seals it to the pump. If you go to AGCOPARTS you can look
it up under the Massey Line, tractors, industrial as a guest user. Page 133

 

[mdkelley]

Thanks, somehow I missed that page in the catalog! Brakes are working much better now, but that little tractor even with the cab on it has no weight on the rear tires with that big loader so the tires just lock/skid in the sand. Guess next thing after getting the steering working will be wheel weights and a ballast box.

 

[mdkelley]

yup, plugged filter and foamy light pink looking oil. I purged the system a couple times and took the filter out and the steering worked great. Going to order a new filter tonight. Thanks again for the help.

 

[Frank Dozer]

i have the exact same tractor and the exact same steering problem. Which and where is this filter?

 

[MKinON]

Inside the power steering pump.

 

[mdkelley]

https://www.yesterdaystractors.com/1852097M1_Power-Steering-Filter_30872.htm

That is the filter most similar to the one I removed. I have no idea if it is the correct one or if it will work for your pump. The measurements matched and mine had a spring behind it.

This post was edited by mdkelley on 09/21/2021 at 05:48 am.

 

[mdkelley]

was a pretty simple job. I detached the hydraulic lines on the front of the pump, loosen the alternator bracket bolt that goes into the face of the pump, and the bottom pump bolt about 4 in below the alternator bracket bolt. pull the pump out (wiggle around the starter, it fits without removing starter) and then as MKinON says, remove the small screws around the pump that hold the tank/cover on. The filter will just fall out once the cover is removed, looks like the spring just holds it in place when the tank/cover is installed.

I most likely did not purge the system correctly... after removing the filter and reinstalling the pump, I just removed the lines attached to the steering ram/cylinder on the right side (same side as pump) and put a bucket under them, then I started the tractor, moved the steering wheel and kept topping off the pump until it looked like the fluid was running clean. I shut off the tractor, connected everything, filled up the pump and started it up, steer lock to lock a few times then shut it down and drained it all again. It definitely isn't perfect but much better than it was. Once I get the new filter I will probably get another 2 gallon jug of the universal hydraulic oil from the local "farm supply" store and purge it again before installing the filter. I am pretty sure someone put the wrong fluid in the system which is probably what ruined the filter, or maybe it was just 50 years old...

This post was edited by mdkelley on 09/21/2021 at 06:01 am.