[Flyer2017]

I have a temperature sensor in my carb. In the past, it showed in the 50's in 30 degree weather and never warmer than 75 or so that I remember in hotter weather. Lately, it will show a temperature warning (AFS EFIS) at 6500 ft and 75% power. Temps will be in the 80's and after landing and taxiing on a 75 degree day they were in the high 90's and even 100 degrees. I recently changed my carb from a Marvel-Schebler MA-4SPA 10-5217 to an Avstar LVC-5-4PA AV10-3678-32 to get more fuel flow on take off for more cooling. The cooling part worked great but the new carb has high temps like the old one. What kind of temps do some of you get in cruise or climb? I don't know anything that has changed. I did plug some holes in the baffles to force more air down thru the fins. Could that raise the temps below the engine? I don't see any Lycoming literature on a 60 hp 0-320 that lists a range for carb temp. Should I reset the temp range for the carb in my EFIS?

 

[D-Dubya]

I'm more familiar with fuel injection, but here are just a couple of thoughts. Someone with more carb knowledge will jump in if I'm off base.

1. If there isn't a carb temp range listed by Lycoming, is this a critical value (within reason)? And if 75 degrees was acceptable, is 95 degrees bad?
2. More efficient engine cooling from plugging the baffles holes means warmer air is coming down around the lower engine and past the carb. If the higher carb temps occurred after you made the baffle changes, then a correlation between the two would appear to exist. Improved engine cooling would seem to be an acceptable trade-off for slightly higher carb temps.
3. There's another post from a guy who has Bluetooth temperature sensors on his tires and wanted to know what the acceptable range was. Years ago, we didn't have the technology to even know what that was. Yes, carb temperature sensors have been around for a while to detect ranges where ice may form; but could this be another case of having so much information available that we have something else to worry about?
4. In the absence of valid information to set acceptable limits in your EFIS, then changing the range would seem to be the thing to do. Especially if it's setting off alerts and causing unnecessary distractions.