Thermostat Falure and Overheating Raptor Engine

[Holdmybeer]

I can fix this for you.

I had the same issue and had to MacGyver it on the water.

From the top of the coolant reservior there is a small 1/4" hose.
Remove it at the reservoir and insert a small funnel and fill with coolant.
It will take forever but mine took 3/4 gallon of premix.
Once full, reconnect to reservoir.
Start the boat and watch Temps. It should burp air now.
Top off the reservior as needed.
Engine should stay cool on fake a lake.

FYI...this procedure is straight from the Indmar manual.