Audible alarm Q

Tafflad

Chief Petty Officer
Joined
Oct 23, 2007
Messages
536
I have a 4.3L Mercruiser (carb) 2007 with Alpha I drive

It has low Hrs, runs well and has full servicing.

This Q relates to Audible alarm .. i.e the buzzer than sounds when you turn on ignition, before engine starts.

Went out for nights skiing .... it last 30 min or so, had the audible Alarm sound as less than 1/2 sec beep ... twice.
Other than that worked fine, as we brought boat back onto trailer as we started trimming up drive the Audible alarm started sounding - continuously ... trimming drive back down made no difference.

As we had finished for the night ... left it at that.

When I got home - usual run on muffs .. and now Audible alarm sounding permanently.
Oil pressure, water temp & charging all OK.
Water flow out of engine is OK.


What would cause this Audible alarm ?
 

rickryder

Commander
Joined
Jun 24, 2010
Messages
2,722
Re: Audible alarm Q

Sounds like the wire for the alarm is shorted to a ground or a sender is bad..... try disconecting the senders and see if it stops.
 

John_S

Rear Admiral
Joined
Jun 21, 2004
Messages
4,269
Re: Audible alarm Q

Outdrive oil level is usually on the alarm circuit as well.
 

Tafflad

Chief Petty Officer
Joined
Oct 23, 2007
Messages
536
Re: Audible alarm Q

anybody able to list all sender (and rough locations) that are 'looked at' by this alarm
 

John_S

Rear Admiral
Joined
Jun 21, 2004
Messages
4,269
Re: Audible alarm Q

anybody able to list all sender (and rough locations) that are 'looked at' by this alarm

I don't know your specific year model, but here is general info that should get you there. The following is based on the warning buzzers that have been on Mercs for many years. You should check the service manual for your engine, to see if there have been any updates or other engine functions monitored.

The instrument senders are different than the warning sensors. The warning sensors are basicly just a switch. You will need to look at wiring diagram and trace out the ones you need to test.

The water temp sensors are in the thermostat housing.

The oil pressure is at the back of the block, behind intake manifold, toward port side.

The drive oil level is on the fill bottle mounted somewhere on engine.

There is none that I know of for alternator output.
 

Tafflad

Chief Petty Officer
Joined
Oct 23, 2007
Messages
536
Re: Audible alarm Q

Thanks sounds like a job for my multimeter tomorrow night.
 

Tafflad

Chief Petty Officer
Joined
Oct 23, 2007
Messages
536
Re: Audible alarm Q

Just a thought ... is it possible to obtain a wiring diagram on line ? .... I only have the 'owner manual' which does not have this.

If so anybody point me to where ?
 

John_S

Rear Admiral
Joined
Jun 21, 2004
Messages
4,269
Re: Audible alarm Q

Just a thought ... is it possible to obtain a wiring diagram on line ? .... I only have the 'owner manual' which does not have this.

If so anybody point me to where ?

Go to Adults Only sticky and follow "mercruiser" trail to SM. I believe you need number 32.
 

Tafflad

Chief Petty Officer
Joined
Oct 23, 2007
Messages
536
Re: Audible alarm Q

Go to Adults Only sticky and follow "mercruiser" trail to SM. I believe you need number 32.

32 says its MPI .... mine is 2007 carb model

would that therefore make the manula I need - :
#25 Engines: GM V6 1998 -
or
#41 Engines: Turn Key Start (TKS) 2004-Newer
 
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