GRSFAST

My Port Side 2004 496ho Sounds A Steady Alarm At 1100 Rpm Or Higher, At Adle (900rpm)... No Alarm...??...all Fluids Are Full And Ok,...water Temp Is Good,...oil Pressure Is Good,..changed Out Fuel Filters,...checked All Plug Wires,..all Appears To Be Ok........anyone Know What Could Be Causing This Alarm??????????????

turnerrd

Have to scan it and see..

GRSFAST

Yep ...thats My Conclusion.....thanks

Nauticall

Finally, someone has determined the answer to this Alarm problem, which seems to be ongoing. THe Crank Position Indicator Sensor was at fault prior to installation, Mercruiser knows this. The computer's used to trouble shoot will NOT detect this, and our sensor was replaced once already in 4th year of use, but however alarm started up again and progressively gets more and more frequent, this controls all of the timing in the engine. In this case our Starboard, again. Merc Mstr Mechanic could not find a problem with repeated service calls, tomorrow they come out again, to look at this part, move it to the other engine and see if it performs on that one. I'm told that is the key to diagnosing. GRSFAST, try Ventnor Marine in Pasadena, talk with Robin about the same problem we a re having in the Formula 40SS. Good luck to all with this engine. Other than this HUGELY frustrating problem, engine's are great. Relatively speaking.

dukenrock

I had a similar issue and it was a cam sensor...

GRSFAST

Had The Engine Scanned By A Local Fellow Jay Who Owns Md Marine Service, And Found The Problem To Be Low Water Pressure On The Starboard Engine.....yep Thats Right A Worn Out Impellor Was Setting Off The Alarm !!.....it Was Pumping Enough Water Pressure At An Idle To Keep The Engine From Overheating ,..but Revving The Motor Above 1100 Rpm Sent A Code To The Computer For Low Water Pressure And Set Off The Constant Alarm Putting The Engine Into Full Limp Mode...the Alarm Would Not Go Off Until The Motor Returned To An Idle...smart Craft Is Good Stuff...i Was Able To Replace The Impellor Before It Shredded And Clogged My System With Debris !! , And Never Overheated My Motor !! Jay From Md Marine Service Is A Great Guy Anyone Needing Any Help In The Md Area Call Him
(410)-320-2495

Nordicflame

iTrader: (4)

Yes this is a chink in the armor on this motor. We chased this problem round and round and finally decided to change out the cam sensor and it ran fine. Trouble started up again 6 months later and it actually showed an active cam sensor error on Diacom. Changed and all was good.
The next year same thing happened but with the crank sensor. Has been fine for over a year now but the sad thing is, it's always in the back of your mind.
My personal 496HOs have not had this issue so guess it's luck of the draw!