The oil pressure gauge at the upper helm position was displaying near to zero, when the engine got warm. This was worrying. At the lower helm position the oil pressure gauge seemed to indicate a normal reading. So what was going on?

Original oil pressure gauge

I thought maybe the oil pressure senders (there are 2) were wired wrong. I tried various options with this.

I thought maybe the oil pressure senders were of the wrong type so I ordered new ones.

2 Oil Pressure senders removed from the engine.

The upper helm gauge must have been fitted later in the boat’s history. The brand is Faria. I got in touch with the tech support at the Faria supplier ASAP. The person I spoke to was very knowledgable and tracked down the problem.

New gauge installed with the old US type on the left.

There are 2 types of senders and gauges. In the USA, the the resistance (OHMS), increases as the pressure goes up. The EU type does the opposite! So there you have it, the gauge on the upper station was reading backwards because it was not compatible with the original lower helm gauge.

The solution was to purchase a new gauge set up for the European standard. As you can see the new gauge shows the reading in bar at the top.