MF 65 power steering question

[sodly]

When I take the activating linkage loose on top of the PS cylinder and push the activator in and pull it out with a vice grip the front wheels begin to move but only just barely. As if there's not enough line pressure. Any ideas why this might be? Normally, if you push the activator linkage into the cylinder the wheels will turn right. When you pull it away the wheels will turn left. Mine only moves the wheels about an inch each way. Hmmm.

 

[Dieseltech]

Is the front end greased well? If bushings are dry system won't turn as it should. Might also be a weak PS pump, low on pressure and flow..

 

[steve19438]

plenty of air in tires ?

 

[sodly]

Yes to all. I'm thinking low ps pump pressure. Is that pump easily rebuildable?

 

[da.bees]

The large bolt with loc-nut on top of cylinder regulat's amount of assist. When set to extreme,cylinder will turn wheels all the way soon as steering wheel is turned just a little. Try adjusting it by quarter turn's until steering feel's right when steering wheel is turned.

 

[TE20-PLUS]

What happens if you jack up the front end so the wheels have no weight on them, and then you try to push the valve in, or pull it out ?


Bill

 

[sodly]

(quoted from post at 16:39:35 06/21/20) The large bolt with loc-nut on top of cylinder regulat's amount of assist. When set to extreme,cylinder will turn wheels all the way soon as steering wheel is turned just a little. Try adjusting it by quarter turn's until steering feel's right when steering wheel is turned.

Yes, there is good movement in the tapered bolt. Enough to activate the inward/outward movement of the cylinder control valve. Even when I push/pull the control valve all the way by hand I get just a tiny bit of wheel movement.

 

[sodly]

(quoted from post at 10:24:13 06/23/20)
What happens if you jack up the front end so the wheels have no weight on them, and then you try to push the valve in, or pull it out ?


Bill

I still need to try this. If I get power assist with the front wheels in the air but not when they're on the ground what does that tell me? BTW, this tractor does have quite a bit of front weights on it so I'm sure that isn't helping matters.

 

[TE20-PLUS]

(quoted from post at 14:27:54 06/23/20)

(quoted from post at 10:24:13 06/23/20)
What happens if you jack up the front end so the wheels have no weight on them, and then you try to push the valve in, or pull it out ?


Bill

I still need to try this. If I get power assist with the front wheels in the air but not when they're on the ground what does that tell me? BTW, this tractor does have quite a bit of front weights on it so I'm sure that isn't helping matters.

If the power assist easily turn the wheels up in the air, but not with the eight of the tractor on it, it tells there is either a big leak in the cylinder from one side to the other, or not enough pressure. Lack of pressure can come from an open safety valve, or partly open, or broken, or a worn out pump. Have you checked the filter ? But, usually if the filter is fully plugged you will get a silly noise from the pump.

Bill

 

[sodly]

(quoted from post at 20:41:24 06/23/20)

(quoted from post at 14:27:54 06/23/20)

(quoted from post at 10:24:13 06/23/20)
What happens if you jack up the front end so the wheels have no weight on them, and then you try to push the valve in, or pull it out ?


Bill

I still need to try this. If I get power assist with the front wheels in the air but not when they're on the ground what does that tell me? BTW, this tractor does have quite a bit of front weights on it so I'm sure that isn't helping matters.

If the power assist easily turn the wheels up in the air, but not with the eight of the tractor on it, it tells there is either a big leak in the cylinder from one side to the other, or not enough pressure. Lack of pressure can come from an open safety valve, or partly open, or broken, or a worn out pump. Have you checked the filter ? But, usually if the filter is fully plugged you will get a silly noise from the pump.

Bill

I did look at the filter inside the fluid reservior and it looked fine. Fluid is old but clean.

 

[sodly]

I jacked the front end up and the power steering worked (by manual activation of the cylinder). As I slowly applied more weight to the front wheels (i.e. let the jack down a little at a time) the steering assist got worse. When the wheels were all the way down I had virtually no assist. Maybe a half inch of wheel travel left and right. Does this sound like a pump issue, considering it seems to work ok with the front wheels off the ground?