Despite good flow out the telltale on a 1984 40 HP Evinrude, the engine was not cooling properly. I had no cooling water exiting anywhere else and my temperature warning alarm went off. Given that this is a salt water motor that sat all winter and most of last season, I suspected and changed the thermostat. No change. I put in a new water pump and that did the trick. All is well now. The biggest lesson I learned is that the telltale flow is not necessarily a good indication of water pressure or the volume being pumped. Thanks to the folks on this board that gave me advice when I posted the problem.
