Does the kit behave differently when the hydraulic oil is cold?
In cold weather the viscosity of the hydraulic oil rises, so the movement resistance of the control mechanism increases; the kit may pull the lever more slowly or with strain. The LFT20 produces at most 10 kg and the LFT54 at most 15 kg of cable pulling force. Run the tractor at idle for a few minutes and normal behaviour returns once the oil has warmed up.
In cold weather two effects add up:
- Oil viscosity: Cold oil thickens, the valve spool and the mechanism move more stiffly. Even pulling the lever by hand becomes harder.
- Battery performance: At low temperature the current the battery can supply falls and the terminal voltage drops. Since the motor's torque production depends directly on voltage, the kit pulls more slowly.
Recommendations:
- Start the tractor and let it idle for a few minutes, circulating the hydraulics by raising and lowering unloaded a few times.
- Use oil of the viscosity class recommended by the tractor manufacturer; do not put in thicker oil for the winter.
- Grease the joints and cable guide points of the mechanism; rust and frozen water increase the resistance considerably.
- Check the battery voltage; a weak battery is first noticed in the cold.
If the strain continues after warming up, the cause is not temperature; look for binding in the mechanism or friction along the cable route. Instead of repeatedly forcing the kit, remove the mechanical resistance.
The full topic: Converting a tractor hydraulic lever to electronic control