Ahhhhh, Sea WATER pump, aka raw water pump.
Remove the outlet hose of the pump, start the engine (For a few seconds) and see if you have a good flow of water. Do this in the water, not on muffs.
If the impeller is over a couple of years old, It needs replaced anyway.
i also took the 2 hoses off that go to each exhaust manifold and it seems like the same flow to each one so why would one side get so hot this just got me puzzled