To replace a water pump on a Massey Ferguson tractor, you will need to first drain the coolant and any residual oil from the engine block. Remove the hoses and belts that are connected to the old water pump, then disconnect the throttle cable and governor linkages, if applicable. Using a socket wrench, unbolt the water pump from the block and carefully remove it. Clean the mounting surface so that the new pump seals properly. Apply thread sealant to the new water pump and reinstall it in reverse order. Be sure to reconnect all the hoses, belts and linkages prior to filling the cooling system.