I have a Evinrude 1976 200hp outboard. This was purchased from someone who had 2 of them on a race boat. Out of the 2 motors, I was able to make one somewhat decent one. Problem--- it keeps overheating at higher rpms.(3500 and up) It has a nosecone on it with low level intakes and the normal intake holes are bondoed shut. The motor does have a jackplate. I know now the history of why someone would want to do this, but it doesn't make sense to me because it seems that it only allows maybe 12% of the water volume that the 8 stock water intake holes allowed. My theory is that the low level intakes allow for enough cooling for cruising at 3000 rpms but when you need/want to go faster the pump just can't get enough water to cool down the motor at 4600 rpms let alone 5500, which by the way I can't attain(4800). Is this a plausible theory or am I missing something? Prop pitch is 14.5 x 19. Engine up dates are as follows:compression 115 give or take a little, new head gaskets, water pump, thermostats, 6 new coils, new fuel lines and a partridge in a pear tree. Also, plugs are ul-77. Can I remove the hose, plug up the nosecone intakes and plug up the two openings that the hose is attached to? Oh, and also open up the original water intakes. It is hard to start, but once it does, it purrs until I decide to up the rpms. Please, comments, recommendations or just yell at me for getting into this. Thanks
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