Auxiliary Hydraulic Unit and Lift Arms

I have a US built MF 135. It has a two-way auxiliary unit mounted with two external couplers. Is there a manual for this unit? Does the hitch work separately from the auxiliary unit? As the tractor is running the lift arms don’t respond on the levers anymore but, as I raise the lever of external cylinder no. 1 the lift arms raise or go down. When the hoses are attached to external no. 2 they work okay.

Yes, there is a manual for the auxiliary hydraulic valve. I will scan it and send it to you. When the controls on the 3 point lift quadrant are set for constant pumping, the left hand lever on the auxiliary valve will then be used to operate the 3 point hitch linkage.

To operate the 3 point hitch linkage with the controls on the three point lift quadrant, take the “Position Control Lever” out of the “Constant Pumping” position. Move the left hand lever on the auxiliary valve to the rear or lift position. The three point hitch can now be operated using the levers on the three point lift control quadrant.The draft control can also be used in this position.

If the left lever on the auxiliary control valve keeps popping back to the neutral or middle position, loosen the lock nut and turn the screw on the detent spring in to put more pressure on the detent spring. I also noticed you have the hoses for the couplers connected to the left spool of the auxiliary valve. Normally when you have one set of hoses they are to be connected to the right spool. That will allow the left spool to be used to control the three point hitch, and the right spool to operate the auxiliary cylinders.