Loss of power and overheating. Mercruiser 4.3 alpha one

[Leothe]

Hello went out on my boat for first time today this year. After 5 mins I noticed a lack of power and temperature gauge in red. I thought this could be impeller problem so I took boat out of water and run on muff and was pumping water well and any of power. However the alpha one leg sounded. A it more noisy that usual. Could it be the gimbal bearing that caused the engine to lack power and take the temperature gauge into the red.
Thanks Leo

 

[alldodge]

Overheating can cause the head to warp and blow the head gasket. Do a compression test to see if that happened

So far as the noise, pull the drive and check the gimbal bearing. Place your fingers in the bearing and rotate, it should feel as smooth as silk