The previous owner was a long-haul trucker and added oil pressure and water temp gauges. For the oil pressure gauge, he inserted a nipple with tee between the factory sender and put the after-market sender on the tee. Unfortunately, he used an SAE-thread nipple that only screwed two threads into the block and it broke, sending oil everywhere. I caught it pretty quickly due to the drop in oil pressure on the gauge, the Yanmar alarm, and the oil slick in our wake. I too the tee off and reinserted the factory sender. The oil pressure gauge is still inop, as a metric to SAE close nipple is hard to find, as equally hard to find as a metric sender unit.
The water temp gauge was added using various tees and nipples as shown in the photo. It works very well...usually running ay 160 or so a low revs, climbing to the 200 range above 3200 or so.
The gauges were mounted to the overhead to stbd of the stereo, not here I would have put them, but it is what it is. The light for the gauges is wired into the running light circuit.
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