Hi Folks,
Jumping into this thread late. The issue for me is my oil pressure warning light and horn started going off today. No leaks that I can see. Oil was a little low on the dipstick but I added some more and now it is a little over full. But still getting the horn. I will check that 10-amp CB mentioned. But anything else I can check?
Thanks,
Jim
#178 "Polaris"
Jim, here's a corrected schematic of the engine and pod circuits (the one in the 310 manual has some errors). A quick description of the oil pressure circuit is: "The lift pump is connected to the "P" terminal on the alarm buzzer, which is also the side of the oil pressure switch that is not connected to 12V (coming from the Pod). On the schematic it says Oil Pressure Switch. That is all part of the (complex) circuitry that runs the lift pump when the glow plugs are energized or when the oil pressure switch is closed, and sounds the alarm the rest of the time."
So if the glow plugs are energized, 12V gets to the lift pump through the 10A breaker. If the glow plugs are not energized, and the oil pressure is low, the oil switch is open, the lift pump doesn't run and the alarm and light go off. When the oil pressure goes up, the oil switch closes and sends 12V to the lift pump (so it runs), and the alarm and light go off. It's complicated, and makes my head hurt every time I look at it and try to remember how it works!!
If your alarm and light are always on, even if the oil pressure is high then either:
-the oil pressure switch has failed, and will not close.
-the connection at the oil pressure switch has fallen off.
-one of the wires is broken or no longer making contact.