My buddy just called with an issue he is having. I believe his boat is an 03 Rinker w/ a 305, fuel injected.
Good boat and he does not abuse it. Apparently last time out engine alarm started coming on intermittently, and became steadier over time. Back to the slip, and checked all fluids, gear oil, engine oil, etc. all good, no overheat either. Also complained motor now does not want to stay running at idle, and cuts out.

So... Not being up do date on his electrical system, my guess is it is probably a bad oil pressure sender. As for the cutting out at idle, does computer cut out ignition if it does not see adequate oil pressure?
I can plug in a manual gage to verify pressure, but just to make sure it is a bad sender, can I just unplug the wire to sending unit to see if alarm goes away?

Also, he mentioned that he had just recently filled up the boat with gas, and was wondering if bad gas or plugged filter would set off alarm, but as far as I know nothing in fuel system would cause alarms to go off, or please correct me if i am wrong with these fuel injected systems.

Thanks,

Rich

I.A.C. Idle air control valve, can almost guarantee it.

The IAC is bad.
http://www.offshoreonly.com/forums/g...rst-alarm.html

Thanks guys.
I'll check it out.
Rich

BINGO
Running like a charm again. Thanks for the help.

Some notes to share and to validate what others have said.

Merc p/n is 862998
Gasket p/n is 27-863112

Local marine shop wanted $135.00 for this valve.
Called NAPA and gave them the Merc p/n. They were able to cross reference the Merc # and give me exact same part for $60.00 Saved 75.00.

Two allen head bolts and a elec. connector is all that needs to be removed. Removing the old valve validated it was shot. Looking at the underside of the assy, you will see the pintle which strokes a valve open and closed. Without being powered, it should be off the seat enough to see daylight through each side. Mine was still fully closed, not allowing any air flow.

The only issue is gasket. The NAPA valve comes with a gasket, but not same type. NAPA gives you a molded rubber gasket which appears intended to fit into a channel on the pad that the valve bolts onto. Perhaps this pad is different on auto vs marine.
The original marine gasket is just a paper gasket which sandwiches between the valve and mounting pad. I was able to reuse the old gasket, and added a touch of sealant for good measure. You could buy the merc gasket if you choose, or just make one yourself.

Hope this info can help someone else. Just trying to pay it forward.