Mercruiser issues with alarm and guardian mode

[Bill Mel]

Replaced the 350 last season with a crate 383 and the boat ran great for a month. The guardian started alarming with water pressure warning at around 3000 rpm. All gauges on console read normal. That was last season. The mechanic (warranty job) looked at it and trouble shot it. It was the end of the season. Launched it this year with what I thought would be no issues. We got a half days use out of it with no issues. The guardian started alarming on water pressure with all gauges still reading normal 158 - 170. Its all happening at 3000 rpm. Its under warranty and still waiting on the mechanic. Has anyone else experienced this? So frustrating!

 

[dubs283]

What is the sea water pressure reading when the alarm sounds?

 

[Bill Mel]

I didn't think to check this year. I monitored last year when it started happening. It was normal last year. I will check and post an update.

 

[alldodge]

Just guessing, but might be the sensor was never replaced

 

[Earl Cordova]

The most common failure on our boat is the water pressure sensor.
It has been replaced 4 times in 16 years.

 

[Bill Mel]

Just guessing, but might be the sensor was never replaced

I hope that it was all new. I bought a crate motor. I hope there aren't any old parts. I ran the boat and all the water pressure readings are normal. Gonna check all the grounds.

 

[alldodge]

Crate motor complete with exhaust or just motor?

If full with exhaust then disregard

 

[Bill Mel]

Crate motor complete with exhaust or just motor?

If full with exhaust then disregard

Yes full. Thanks.