So did you ever determine if it was actually overheating?

Did you smell coolant or anything?

An infrared thermometer is a nice tool to have handy, just aim and shoot for temp readings most anywhere:

http://www.summitracing.com/parts/oes-25245/overview/

But I suppose if it's cooling down before you even get off the highway...did you try to reproduce hot reading at high rpms while in park?

brian

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https://tinyurl.com/yynpj4v2

just for ducks you might want to check for combustion gases in the coolant. if you have a leaking head gasket or water jacket you could be getting those gases into the cooling system and heating up the coolant.

A bit of a stretch but it happened on my flathead without any water leaking into the crankcase or oil into the coolant.

I don't know where you get litmus paper anymore or if it works with coolant but it did with water.

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hot rodder at heart!

I haven't road tested with the new gauge, hopefully tomorrow.

I should check the temp with a laser, but it cools down cools down instantly when I slow down. However I was joking with my friend that I should take my hood off and have him sit on the fender and laser the engine as I drive down the freeway... It might yield constructive information.

More update tomorrow.

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These ones go to eleven...

Make sure you take pix if you do that!

The gauge was not accurate. I will road test as soon as it dries up outside.

B

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These ones go to eleven...

I see a flaw in your plan: you live in Oregon. (quack!)

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一期一会
Too many people who were born on third base actually believe they've hit a triple.

Quack indeed! It wont surprise me if that road test occurs in three weeks.

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These ones go to eleven...

I test drove the car today. Letting the car idle from a cold start it never tops 160. On the freeway it hovered just shy of 200, coming off the freeway and driving around town it cools back to 190 and after that I let it Idle and it cooled to 185. The outside temperature was in the upper 50's today.

I disconnected the vacuum advance and ran the same route and the results were unchanged. The thermostat is tested and installed correctly. The water pump is good.

The old gauge was bad, but it seems that the car is running warm for these conditions?

Crud in the block? Running too lean? Too much mechanical advance?

By the way this little 170 really pulls, it has more power than I expect and Idles like silk. No pinging either.

Hmm,
B

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These ones go to eleven...

None of that sounds out-of-line.
I don't agree. Read this.
Of course it's possible you've got crud in the block or a too-lean mixture (read your spark plugs; what do they say after a highway run?), or exhaust restriction. But any of those, especially lean mixture and exhaust restriction, will tend to cause pronounced ping, and you say you don't get any. Excessive spark advance will cause ping, but not overheating -- insufficient spark advance (retarded spark) will cause overheating.
Then…drive and enjoy!

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一期一会
Too many people who were born on third base actually believe they've hit a triple.

Good to hear it's all good....Don't forget to check that vac advance canister...seems strange you didn't notice any difference,it could have a leaking diaphragm.

Thanks Dan! I will drive and enjoy and not worry.

B

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These ones go to eleven...