How cool?
When I first put my boat in and ran it...it was shooting a stream about 3 ft. out the outlet. I thought cool, I have excellent flow through my cooling system. I was having a little trouble getting my engine to run really well. Then I thought about it...what if my engine has not had the chance to warm up to normal operating temperature? I lifted my water pickup a little and cut down a little on flow...this helped! The engine ran much better after that. I guess I was cooling the engine to much and not letting the engine actually warm up to where it needed to be. I've seen boats in pictures that are just flying with these highly modded race engines and just seeing the water kind of spitting out the outlet not streaming. I figure these guys know what they are doing and aren't burning up their engines.
How do you know how much water to flow through the cooling system? Experiment as I did?