1999 Baja 342 with twin 502 MPI with 132 hours.

We ran it on a hose before buying it.

Dunked it for the first time last night. Never left the dock because port motor alarm is sounding. All fluid levels look good. Oil pressure and water temp looks good. Seems to run fine, sounds good. I'm not sure what else to look at. What other functions is the alarm attached to? Could a sensor be bad? How can you tell?

The alarm on 502mpi's only goes off for low oil psi, high water temp or low drive fluid. Chances are its the drive lube sender. It has a floating switch that if it sinks to bottom sets the alarm off. It may have gotten stuck. Unplug one of the wires going to the bottom of the drive lube reservoir and see if the alarm stops.

Thanks. I'll try it tonight.

If you give up, I will buy both your alarms

Well it's not the drive lube alarm. Unplugging one or even both the wires didn't stop it.

I'm thinking it's one of the other two. Can anyone tell me where they are or where to buy noew ones?

Reason I think it's the sensor is because 1- oil pressure and water temp gauges look good and 2- alarm sounds immediatly when starting the motor. No way it's actually hot enough to set it off.

Alarm wires are tan with a blue stripe.

The water temp alarm sender is in the front of the intake manifold. The low oil pressure one is down by cylinder 7 where the remote filter assembly connects to the engine.

gracias!

Its also possible it could be in the wiring. I had that happen to me. A splice where the alarm wire went to the drive lube wire came apart and one of the wires was hitting the intake manifold and causing it to ground and set off my alarm. Took me forever to find the issue.