Just a couple of photos from the first day of filming we did for the Ferguson TE 20 Hydraulics DVD. In this shot the lighting and camera were focused on the work bench as we dismantled the pump.
Now take a look at the colour of the transmission oil that came out.
The oil clearly hadn’t been changed for years and water had emulsified with the oil to make this yellow creamy fluid. There was also half an inch of corroded aluminium deposits and dirt in the bottom of the oil reservoir.
The mixture of oil and water is caused by condensation forming in the transmission housing and then dripping into the oil reservoir and mixing with the oil. This is the reason for regularly changing the oil even if the tractor isn’t been used for many hours a year (like many Fergusons that are owned by enthusiasts). In fact the less the tractor is used, there is an argument for changing the oil even more often (due to the increased likelihood of condensation forming).