1. Park the Massey Ferguson 50 on a level surface and turn off the engine. Allow the engine to cool to a safe temperature and disconnect the negative battery cable with a wrench.
2. Locate the lift valve on the Massey Ferguson 50, which is on the right side of the hydraulic pump. Place a container or an oil draining system under the pump to catch the hydraulic oil draining from the pump when you remove the valve.
3. Remove the retaining nut and washer from the valve with a wrench, then slide the lift valve out of the pump.
4. Install the new lift valve into the pump and replace the retaining nut and washer. Tighten the retaining nut firmly with a wrench.
5. Reconnect the negative battery cable with a wrench, then turn on the engine. Test the lift valve to ensure it is working properly and that the hydraulic pump is functioning as it should.