MARITIME COMMUNITY

The old systems details was left out in the last post and I was aksked to give more details on how it worked and why it failed.

Here are some of the working of it;

This system would use air as a medium, so the diaphragm separated the oil from the rest of the system. If it was full of diesel fuel, it would give a false reading because the ‘head pressure’ (the height of the gauge above the bottom of the tank) would introduce an offset equivalent to whatever volume of oil in the tank at the height of the pressure gauge. Effectively, whatever height the pressure gauge was, it would read zero whenever the oil was at the same level as the gauge, or negative when it was below the height of the gauge.

The failure probably occurred when the diaphragm or fittings in the sensor leaked and filled it with oil.