Cormiers Cove
Member
1959 MF 35 with 2 spool valve with levers in front of the seat.
As soon as I start the tractor the lift arms go all the way up and the pump continues to try and lift further.
I bought this tractor a month ago and the previous owner used the left lever on the 2 spool control valve in front of the seat to lift and lower the 3 point hitch. The quadrant position and draft levers did not work. I thought it might just be the linkage for the quadrant levers being to the rear of the roller on the vertical control valve lever. But as the top link spring had much play and the boot was dried out and cracked we decided to remove the lift cover and replace the spring, and rubber boot along with a new nut as the entire spring assembly needed be serviced and adjusted as per the Service Manual. We manufactured a wrench for the nut.
We set the position and draft levers on the underside of the cover to the correct 3 pound setting and also set the eccentric roller against the position lever as per the Service Manual. We drained all the old fluid and replaced the filter and bottom O-ring under the strainer. We also decided to remove the 2 spool valve control in front of the seat and replace it with a brand new cover plate since that 2 spool valve was leaking fluid when used. We replaced the O-rings on the stand pipe and put a new one on the new cover plate.
We lowered the lift cover with a chain hoist making sure the Position and Draft levers were in front of the roller of the vertical control valve lever. The standpipe was put in the correctly and the we bolted the cover down without a gasket or sealer just to make sure everything worked correctly. We added new hydraulic fluid to just below the bottom bolt hole on the dip stick cover.
With the dipstick cover off we started the tractor. I made sure the position control quadrant lever was at the lower end of the control range. Right at where the draft response range starts. I made sure the draft was set at the sector position between the little dots on the quadrant.
The lift arms immediately lifted upon starting the engine and the pump continued to try and lift further. It doesn't matter where we move the quadrant levers. Nothing happens. Evidently the hydraulic fluid is being pumped into the standpipe as the lift piston is working.
One thing I recall when we tried the 2 spool valve levers prior to all this was that when we locked the left lever in front of the seat all the way back the pump continued to try and lift the arms further. The pressure caused fluid to leak out by the valve levers in front of the seat. This was one of the reasons we wanted to replace this 2 spool valve with just a cover plate This was not suppose to happen as we were told that if locking the left lever back that we could use the quadrant levers to raise the lift. But the quadrant levers were not working.
I'm guessing there was a problem with the control valve or something at that time when locking the left lever back did not allow the quadrant levers to work.
What should I do next to troubleshoot this issue? Control valve replacement? I read something about an oscillator but have not idea where to look or how to check this.
Thanks
Scott
As soon as I start the tractor the lift arms go all the way up and the pump continues to try and lift further.
I bought this tractor a month ago and the previous owner used the left lever on the 2 spool control valve in front of the seat to lift and lower the 3 point hitch. The quadrant position and draft levers did not work. I thought it might just be the linkage for the quadrant levers being to the rear of the roller on the vertical control valve lever. But as the top link spring had much play and the boot was dried out and cracked we decided to remove the lift cover and replace the spring, and rubber boot along with a new nut as the entire spring assembly needed be serviced and adjusted as per the Service Manual. We manufactured a wrench for the nut.
We set the position and draft levers on the underside of the cover to the correct 3 pound setting and also set the eccentric roller against the position lever as per the Service Manual. We drained all the old fluid and replaced the filter and bottom O-ring under the strainer. We also decided to remove the 2 spool valve control in front of the seat and replace it with a brand new cover plate since that 2 spool valve was leaking fluid when used. We replaced the O-rings on the stand pipe and put a new one on the new cover plate.
We lowered the lift cover with a chain hoist making sure the Position and Draft levers were in front of the roller of the vertical control valve lever. The standpipe was put in the correctly and the we bolted the cover down without a gasket or sealer just to make sure everything worked correctly. We added new hydraulic fluid to just below the bottom bolt hole on the dip stick cover.
With the dipstick cover off we started the tractor. I made sure the position control quadrant lever was at the lower end of the control range. Right at where the draft response range starts. I made sure the draft was set at the sector position between the little dots on the quadrant.
The lift arms immediately lifted upon starting the engine and the pump continued to try and lift further. It doesn't matter where we move the quadrant levers. Nothing happens. Evidently the hydraulic fluid is being pumped into the standpipe as the lift piston is working.
One thing I recall when we tried the 2 spool valve levers prior to all this was that when we locked the left lever in front of the seat all the way back the pump continued to try and lift the arms further. The pressure caused fluid to leak out by the valve levers in front of the seat. This was one of the reasons we wanted to replace this 2 spool valve with just a cover plate This was not suppose to happen as we were told that if locking the left lever back that we could use the quadrant levers to raise the lift. But the quadrant levers were not working.
I'm guessing there was a problem with the control valve or something at that time when locking the left lever back did not allow the quadrant levers to work.
What should I do next to troubleshoot this issue? Control valve replacement? I read something about an oscillator but have not idea where to look or how to check this.
Thanks
Scott