Chrysler 440 Overheating

I recently installed a 1975 Chrysler 440 in my resorter and it is running hot. The engine is set up with a Sherwood raw water pump that cools the exhaust manifolds and a bidirectional circulating water pump that cools the engine. When I started up the engine, the engine ran up to 165F and I shut it down. I removed the thermostat and started it. The raw water pump had strong flow. There was no water flow by the circulating water pump. I removed the impeller and it looked fine. Both these pumps draw from a common suction hose. My question, does the circulating water pump need priming. The engine has been sitting so it was dry.

Any ideas.

I don't think so... It may not help you in this case but I was told once that 440's are difficult to cool because you have to
treat them as 2 4 cylinders plumbing wise....??? Never owned one just came up in conversation with a woman at Glenwood marine

We have a 72 Resorter with a 440. About 15 years ago I changed the thermostat and had high temperatures too. Turned out I had put a 160 degree thermostat in when I should have put a 140 degree thermostat in. Corrected the thermostat to 140 degree and problems solved. The Chrysler engine manual says 140 degree for RAW WATER and 160 or 180 for FRESH WATER; type for both is Pellet.
Good Luck
Jeff