Everything rubber/plastic/paint attched to the manifold would be completely melted if it got hot enough to damage the casting... Most likely freeze damage you didnt preiously notice or manufacturing defect. Do you have water in the oil ?The boat was out 2 weekend ago and ran just fine with no problems. So I wouldn't think it would be a freeze problem. I wondered if it might have sucked something up or one of the connecting hoses collapsed.
motor had to be hotWhy would a hole get blown in an exhaust manifold with no kind of warning? Motor never got hot but it was like the manifold wasn't getting enough water maybe?
That's the crazy thing. Motor never got hot nor did the other manifold. I will start with the lines that feed this manifold and go from there.that is what happens when you run out of cooling water and your exhaust goes from 200F to 1500F, then a little drop of water hits the casting and rapidly cools it.
so lets go back to the first post.
motor had to be hot
start at the cooling system, do a compression test, and replace the manifold and all the burnt rubber bits.
I didn't have any kind of gauge on the manifold but you wouldn't want to keep your hand on it longer than a few seconds. I would say it would burn skin.All motors exhaust runs a bit hotter, but in the water you should always be able to keep your hand on it for a while. It higher rpms they even out.
Your saying its hot enough to burn skin?
I'm not sure why you say the port side has least resistance?Water flows the path of least resistance, so port side is a bit cooler. You can hold your hand under 120* water all day, but 125* hurts some
Me neither and have not accomplished flow dynamics to prove, just all are that way. Water comes in and the circulating pump is rotating CW from the front of the motor, so my pea brain believes this helps it move to the port sideI'm not sure why you say the port side has least resistance?