Central FL

Donzi I live in the Tampa bay area, not sure if thats close to you..If so I could give you a hand. Either way go by Harbor Freight and buy an infrared temp gun. Put the boat in the water and idle around and point gun at ex manifolds . Not sure of the exact temps to look for but probably 140-170 ish range. If the motor in question has BOTH manifolds hotter than the other one then its probably a bad water pump or clogged intake. If only one manifold reads higher then you might have a bad manifold. The temps from port to starboard on the same motor will usually vary about 10-15 degrees or so away. Not sure what Manifolds are on that motor but many merc manifolds that are 2 piece have several different gasket options. Some have restrictors built in them.They could be in backwards or the wrong restrictor or not even needed if they are in there. Not a merc recommendation but I have had a couple motors where the manifold temps from side to side were way off. Even with new water pump and new manifolds. In those cases I put restrictors on one side and left the other side open. I Have a few other tricks but that will get you started.

Thank you for the info and heads-up. The plan is to put it in the water for now. I do have an IR thermometer and will see what the temps show. I'll let you know. ty