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Carb Air Temp Sensor: What's the best method?


Boise ID area
Seems like a novice question, and it probably is, but the plane has a Carb air temp gauge (and an OAT).

When flying older planes, it was the 'use carb heat when reducing throttle to idle'. And of course when losing power on a wet cold day.

But now with information available I can see, for example, OAT is 34F and the carb is 28F. Another data point I noticed, when pulling back to idle, even on a cold day, the carb air temp will increase, I guess due to the less air intake and the temp of the engine/carb.

So my question is; how best to use this technology? Any thing new to do different or stick my many years old training?
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I had a carb temp gauge on my 180 for 15 years and ignored it the whole time. Literally. The needle was in the yellow zone 100% of the time. I never found it useful. When I added an EDM I included carb temp so I could test the theory that a little carb heat would balance cylinder temps. It didn't. So in total in 10 years I've used that one for about 1 minute. And that 10 years ago. Not a hater, not a fan.
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On my particular Continental engine it is pretty helpful. In high humidity conditions my plane makes a lot of ice and I have found that being proactive based on the temps helps as it can escalate quickly. I've flown with other guys with Pponks that never run carb heat and have no issues, but my carb runs really cold (there is a whole thread about this somewhere on here).

Thanks for the responses. I did search and read the results. It was interesting that Pponk' 180's were all different with carb icing and that Continental engines are prone to icing more than the Lycoming's.

The engine is a 340 so I'll just keep using carb heat as per SOP.

In my 180 with an EDM900 engine instrument package, I hooked up carb temp and referenced it often. That airplane with an O-470 was a carb icing mofo. Keeping the carb temp at 40F smoothed all flight regimes and evened the temperatures. Carb temp information was critical to flying that airplane.

Probably something to do with the induction system shapes and charge scavenging of that engine design.

Beaver engines need the carb temp at 4C (40F) (!) to avoid carb ice. Its in the flight manual. It is in my scan while driving them.