Port Engine/Guardian Alarm

[spirt320]

Hello all, just purchased a 2013 341 with 8.2 HO MPI's with 26 hours on it and selling my 320 but I know this is a great forum and will not leave. Since most of these boats all use the same running gear I know there will some great answers or areas to look at from CSR members. So a few weeks ago while testing her, at various RPM's around 1500 to 2000, the port motor would kick in the guardian alarm stating that engine power was limited and critical-overtemp. This happened over and over so we just docked her. This vessel has been sitting for about five months and had original fuel we believe in her for about two plus years and this was the first time she had moved since then. A few days later I met the selling broker at the boat and we took her out and nothing happened, no alarms. A few hours later we took her out again along with my boat techs who ran her through everything and again nothing. Later that same day, the broker had put some new fuel in her since we pretty much used all of the old fuel. And a few days later, took her out again for about 15 minutes and again nothing. I was very happy. Last week we closed on the purchase and I had my techs do a full annual service on her last Thursday so we would start fresh. We go to take her out this past Saturday and once again, over and over, getting the same alarms. Meanwhile all of the time, and during the previous times, all of the gauges look good and so do the readings on the vessel view. When you go to the alarm history it says things like over-temperature or check for plugged inlet, water pump may be faulty. But again, all readings look good.

Any ideas? My techs should be looking at it tomorrow or Wednesday, but trying to get a jump on it. I am thinking maybe a bad sensor or bad sensor connection/wire. Thanks in advance!

Greg

 

[sdleo26]

Check the water pressure sensor; its typical that they get clogged with little bits of debris. blow it out and put back in. If you still get alarm, replace sensor it's typically between 60- 90 bucks pending on where you source it.

 

[spirt320]

Not familiar yet with these newer 8.2 HO Mags, does anyone know exactly where the water pressure sensor is? What it looks like etc... I cannot for the life of me find a diagram or schematic online and have gone through all of the boats docs and manuals I have. Looks like my techs may not be able to make it out there this week, so I would love to try and tackle this myself. Also, if anyone knows the part no. for the sensor, that would be great. These are 2012/2013 8.2's.

 

[sdleo26]

If it's a v drive it is more than likely on the tranny cooler ; see link below, part 25 on diagram

http://www.mercruiserparts.com/Show...Transmission+and+Related+Parts(Hurth+630/800)

 

[spirt320]

To close this out and for others to use as reference, the problem has been solved. The poppet valve on the port side of the port motor was stuck. That part has now been replaced and all is well.

 

[bfernald0]

I just had the EXACT same problem Saturday evening on my starboard motor. An 8.2 ECT Horizon engine with 150 hours. New in 2019. Engine overtemp alarm but all of the gauges looked fine. The next morning, I opened up the engine hatch and the starboard exhaust manifold on the starboard engine had clearly gotten HOT. Local mechanic suggested the "poppet valve" was stuck. Had no idea there was such a thing on the bottom of the manifold. Will update if that's the answer.