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No I do not know what the temperature of the engine is. I have been running it on a test bench with a smaller size prop </span>and it seems to be breaking in nicely. Its hot. Its just that I cannot keep the muffler on. I have longer bolts and am going to wire them.
On the subject of engineering. Anytime anyone, including engineers, make an extrapolation of observed data, its questionable.
One of the worst extrapolations you constantly hear is,''I have been doing this for years and I have had no trouble''. The basic problem is the environment you are in will probably not apply in all cases. It will have more credence if the statement is ''the data collected by all people in this country finds this true''. But then you are getting close to what is in the engineering handbook
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That pretty much sums it up. The engine is not getting adequate airflow and is getting hot. What does your engeneering book say about thermal expantion of different alloys in different enviroments?


I decided my last sentence was a little over the top so I deleted it and offer appoligies to anyone it may have offended.


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I realize I should be doing something to reduce the temperature but the instructions say to bench run it for 1 hour. I like to follow the instructions of the people that made it. They know a bit more than anyone else. They have tested a few more than anyone. I have a smaller prop to reduce the load and it I don't run it wide open. It seems to be responding nicely. If it don't I will just send it back and say I followed instructions.
I have not checked an engineering book about thermal expansions. Thermal dynamics is a very complex subject that I did not study in college. I think if I should need expertise in that area I will seek out someone that has and get their advise.
I did talk to an ME about the depth of thread requirement of a steel bolt in aluminum block. He said the coefficient of expansion of steel is less than aluminum so the clearance would increase with heat and result in a loose bolt. He said I should use an aluminum bolt so the clearance would remain the same at all temperature. Then the bolt would stay tight. I think that is the problem with the bolts in the exhaust. They are a steel bolt in an aluminum block. At least I think they are steel.
By the way do you have a spelling checker? If you don't, maybe you should get one.