Ron White wrote:
My boat has Smart Craft gages , so I am not up on the warning lights
operation. However, there are some things I can tell you that may help,
The engine oil reservoir must be completely full. No air space at all. This
is accomplished by filling it all the way and as an added measure, cranking
the engine with the cap loose and letting the oil from the remote oil tank
flow till it coming thru the threads of the loose cap. Tighten the cap while
it is overflowing and you will be assured of a oil system that is purged.

I had an older model with a sticky float switch in its internal
reservoir, and that, plus it having been a rough trip, bias me
towards suspecting the sensor. I don't know how air could have
been introduced into the system, but if I can purge it without
specialized tools I can perhaps rattle the sensor manually a
little and see if the problem goes away.

That may your problem, or maybe not. FYI the engine is not oiled from the
compressor oil, the spent compressor oil does enter the air side of the
injection system and add some lubrication, but the primary oil for the
engine is injected into each cylinder's crankcase. The are seven injection
points. One in each of the cylinders and one to the oil pump.

It's tempting to blame the sensor, but the cost of being wrong
is pretty steep. I've had conflicting advice on whether this
injection system is compatible with the premixing oil in the fuel
in case the engine truly isn't getting lubrication.

Too bad if it's not, as that was cheap insurance in situations
like this.

I think ( I haven't researched this) that the only feedback the warning
lights get is oil level in both oil tanks, and switching to the oil pump.
There is no way to know if oil is flowing as the computer just knows if the
oil pumps operation is switching on and off properly. So, save a switching
error, the problem is oil levels in either tank as well as ail space in the
engine oil tank.
Hope this helps or getting really optimistic, solves your problem.

Well, since I'm looking at a tow if I can't solve it anyway, I
suppose I can take a stab at purging the system. All I need do is
put that cap on loose, and let the engine run until oil comes out?

It doesn't rely on positive pressure in the internal reservoir to
feed the oil pump?

ps, if these thing don't help, you need to have the engine connected to a
Mercury DDT at shop or freind's, that is the only way to check switching to
the pump. Also ,again, you could go thru the self priming opertion and
listen for the injection pump to run.