Overheating issues again

[tdalmany]

I have a Cobalt 2015 220S with the Mercruiser 350 Mag. I am getting an alarm and the boat shuts down into guardian mode. This just started happening. The boat has 226 hours on it. New impeller two years ago. I took the boat to a marine mechanic and he says the codes the boat is throwing are hot manifolds and he thinks the manifolds are not getting enough water and could be clogged? He wants to replace two manifolds but I don't think that is the issue. I have only run the boat for recreation in fresh water lakes and rivers. Does anyone have any experience with these issues and how to resolve.

[AsLan7]

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So glad you found us tdal….

Pretty difficult to diagnose over the internet.

We had a similar issue on our 263. It ended up being a corroded connection where the transom and the outdrive meet. Specifically it was a fitting used where water is pumped through this location. Air was being sucked into this connection causing a loss of cooling.

Any pics?

And welcome aboard mate.