Engine Alarm Help!

[Batwing]

Hi All,
I own a 1999 Carver 350 Mariner with twin Mercruiser 5.7 Mercruiser 350 Mag Mpi engines. My port side engine has an engine alarm that starts beeping approximately 15 seconds after starting. Does anyone know how I can determine what this engine alarm is alerting me to? Is there anything I can reference to troubleshoot? Appreciate any feedback, thank you.

Steve

[bud37]

I can't remember whether that is specific or general, do you still have the engine manuals with the boat ?......check online for your year Mercruiser engine alarm explanations, you may still find them.
You may have to find a mechanic to hook up to the ecu's for active codes and in DTC's in memory. Hopefully someone here has some info to help you.
Can you say how many beeps, or is it a continuous alarm....also can you say with certainty it is not the fume detector ?

[tomschauer]

The alarm on a 1999 will sound on high engine temperature, high transmission temperature or low engine oil pressure.

[Batwing]

Thanks for feedback.

Don't have original engine manual, but have downloaded some PDF's online for some reference.

Can't say for certain it's not the fume detector, so I'll have to look into that.

Alarm is continuous and engine temperature gauge reads normal and the oil pressure appears in the normal range. How do I determine high transmission temperature?

Thanks

[bud37]

QR_BBPOST Alarm is continuous and engine temperature gauge reads normal and the oil pressure appears in the normal range. How do I determine high transmission temperature?

Curious.....did this alarm just start after working down there on the thru hull ?

[Batwing]

Bud37,
No, it's been like this for awhile. I had trouble starting the Port side motor and after replacing plugs, rotor and distributor the engine fired up great, but then alarm started going off approximately 30 seconds to a minute after starting.

[bud37]

The reason I asked......sometimes things get bumped, broken while maintenance goes on.......big feet..
Check all your connections , plugs, keep plug wires away from grounds especially the distributor ground, and other wiring etc....especially the connectors on the trans and the underside of the engine block ( knock sensor ). I don't know what a solid continuous engine alarm is telling you, you may have to get someone to hook up to the diagnostic port. Cross off all the easy stuff first.

Seems like engine temp and oil are ok.....but there are other parameters being monitored by the ecu.

[Batwing]

Thank you bud37.

[Midnightsun]

My gut feeling is the oil pressure monitor wire got knocked off or broken. There normally is a small delay when ignition is activated and after a bit (like your 15 seconds) and if it does not measure oil pressure it will sound. Not saying for sure this is your problem but something to look at for sure.