continuous alarm 4.3 Merc

[[email protected]]

I have a 2006 Mercruiser 4.3. the motor alarm recently started going off. it starts when +3500 rpm and I'm on plane @ 20-30 mph. goes away when I slow to 2000 or so rpm

Temperature (by indicator) goes from 120 @ start to ~ 170F and holds. Oil pressure goes from 40 psi @ idle to 60 @ +3500 rpms. Lower unit oil reservoir is full and I've removed the wires to that sensor.

is there a way to isolate and check inputs to the alarm to see what is setting it off?

any suggestions would be appreciated

 

[o2batsea]

Low oil pressure sensor is your issue

 

[[email protected]]

Low oil pressure sensor is your issue

thanks

any value to changing temperature switch as well?

 

[Docksidemarineservices]

How about posting your serial number.... I get you have a 4.3 but, which 4.3?

 

[Bt Doctur]

could install a mechanical gauge

 

[stang32]

the overheat sensor wires run through the thunderbolt ignition module depending on the year. it has been known to cause trigger the alarm unwarrented. post the serial to determine if this engine has this particular module.

 

[[email protected]]

thanks for your help. i look forward to more input
s/n 0W371724

Model # 4-211025T T

 

[chs]

take a look at this post/thread, it answers a lot of your questions, and based on your serial #, your ignition system is the one with the alarm running through it.

https://forums.iboats.com/threads/mercruiser-audible-alarm.730433/