After 8 days of cruising on sailboat, 50 hp Yanmar diesel (with only 904 hours on it) running 50 hours nonstop on offshore leg of journey and the oil pressure starts declining over a couple of hours.... from 80 to 0. The way the gauge needle was acting (needle not steady but continuous up and down readings...until eventually it was just down) I felt confident it was either the gauge or the send unit. But since I didn't know for absolute sure it wasn't a failing oil pump, I kept an eye on the engine temperature which never wavered. Ended up going another 5 hours with 0 pressure on gauge. I presume if it really was 0 pressure the engine would have seized within a minute, yes ? (in fact the reading was less than zero...bottom pegged)
The question is, does this sound more like failing send unit.. or gauge ?
The question is, does this sound more like failing send unit.. or gauge ?
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