Rick. Id love to give you an answer to that question but idk what your talking about. Just a regular mercruiser 4.3 manifold to a 4” riser and then to the exhaust elbow. Im new to this owning a boat thing.
Reason I ask is the standard Mercruiser V6 Alpha 1 exhaust has the manifolds going to risers into the Y pipe where everything comes together before splitting into main passage to propeller and the two idle relief ports.
I think maybe you need a new mechanic who knows something about mercruiser. From all appearances when he told you:
"The guy at the marina said the side thats heating up is putting out alot of water. The other side only kinda spits out water. He said the side that just spits water a little at a time was the way it’s supposed to work"
Frankly, if he is looking at water out the back of the boat, then he has never worked on Mercruiser exhaust. You cannot tell anything by how much water is coming out of either side. That is so dependent on how level the boat is. It just doesn't tell you a thing.
