Captain Dirty
Platinum Member
After attaching the snowblade to the FEL of my L45 with dealer-installed 3rd function valve, pressing the "A" button moved the blade left, pressing the "B" button nothing. I switched the hoses; A moved the blade R, B-nothing. Shut off the engine but left the ignition on; A produced a clunk that I took to be the solenoid, B nothing. Obviously there is a problem in the 3rd function solenoid valve.
Electrically, a latched relay "arms" the A and B buttons. Pressing a button activates a relay that sends current to the corresponding coil. Mechanically the energized coil moves an armature in a tube. The armature moves a pin that moves the spool to direct the hydraulic fluid. The spool is centered in an open center position by two springs that return the spool to neutral when the coil is not energized.
The connectors to the coils are 2-wire. The power wires to each coil show 14V and 0 V when the corresponding A or B button is pressed or released. The ground wires to each coil show continuity with the tractor chassis. Each coil shows 0 ohms on the 100-ohm scale. I think that is normal as I swapped the coils with the same results, A works, B does not. I also (perhaps unnecessarily) swapped the relays--same results.
Early on I rapped the solenoids with a mallet to no effect. Each tube has a pin on the end that manually pushes the armature. I cannot depress the A side. When I depress the B side, the spool moves and the plow angles, albeit slowly.
When I bought the tractor some years ago I followed conventional wisdom that getting a 3rd function at time of purchase was a better move than adding it later, but the function remained unused till now. Based upon my findings, I believe that the manual pin on the A side is frozen but the armature moves, and the armature on the B side is stuck so that the force of the manual pin will overcome the stiction while the force of the coil field will not.
Have I overlooked something I can try to get the valve working? Replacing the valve will be a hassle I do not want to attempt in Winter. I can manually angle the plow in the B direction by dismounting and pressing the manual override pin. TIA
Electrically, a latched relay "arms" the A and B buttons. Pressing a button activates a relay that sends current to the corresponding coil. Mechanically the energized coil moves an armature in a tube. The armature moves a pin that moves the spool to direct the hydraulic fluid. The spool is centered in an open center position by two springs that return the spool to neutral when the coil is not energized.
The connectors to the coils are 2-wire. The power wires to each coil show 14V and 0 V when the corresponding A or B button is pressed or released. The ground wires to each coil show continuity with the tractor chassis. Each coil shows 0 ohms on the 100-ohm scale. I think that is normal as I swapped the coils with the same results, A works, B does not. I also (perhaps unnecessarily) swapped the relays--same results.
Early on I rapped the solenoids with a mallet to no effect. Each tube has a pin on the end that manually pushes the armature. I cannot depress the A side. When I depress the B side, the spool moves and the plow angles, albeit slowly.
When I bought the tractor some years ago I followed conventional wisdom that getting a 3rd function at time of purchase was a better move than adding it later, but the function remained unused till now. Based upon my findings, I believe that the manual pin on the A side is frozen but the armature moves, and the armature on the B side is stuck so that the force of the manual pin will overcome the stiction while the force of the coil field will not.
Have I overlooked something I can try to get the valve working? Replacing the valve will be a hassle I do not want to attempt in Winter. I can manually angle the plow in the B direction by dismounting and pressing the manual override pin. TIA
