1979 Johnson 9.9 cooling problem?

I have a 1979 9.9 Johnson short shaft. The top of the cylinder head temperature reads 170-180 degrees after a few minutes of full throttle operation. The exhaust cover side of the engine reads the same. The telltale is hot to the touch, not scalding. The telltale stream isn't very strong, the exhaust shoots water out like crazy. The motor starts and runs well the whole time, the telltale cools to lukewarm at lower rpms. I replaced the water pump and there was no change. The head gasket was replaced last year and at the time the person who replaced it took out the stat saying it wasn't needed on this motor. So my questions are A) is this motor running too hot and B) if it is running hot what are the things I can do to fix this problem. This was my grandfathers motor so I would like to keep it running as long as I can. Thanks for the help.

Re: 1979 Johnson 9.9 cooling problem?

With no stat in place it should be running much cooler than it is. My suggestion would be to drop the lower unit, hook a water hose to the water tube and see if it blows anything out. I would probably take it a step further and remove the water jacket on the head and look to see if the passages are running free or blocked. Once you get it figured out I would put a stat back in it as it was designed to run with a stat at approx. 140 degrees F. There is a rubber grommet at the top of the water tube that can collapse and cause circulation problems as well. You must remove the power head to get at it. It used to be written about frequently but not so much lately. You must get the temperature down before you cause damage. Best of luck. Rick.