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Anyone with a Zenith carb install a temp probe into the upper throat of the carb?
Any reasons not to?
There is a brass plug just above the butterfly that could conceivably be drilled and tapped to fit the probe. I had a carb ice event last summer and would like to be pro -active on preventing another episode.
Thanks,
Mike

Mike53 wrote:Anyone with a Zenith carb install a temp probe into the upper throat of the carb?
Any reasons not to?
There is a brass plug just above the butterfly that could conceivably be drilled and tapped to fit the probe. I had a carb ice event last summer and would like to be pro -active on preventing another episode.
Thanks,
Mike

Hi Mike,

"Anyone with a Zenith carb install a temp probe into the upper throat of the carb"
No idea

"Any reasons not to? "
Cant see how it will help/inform you.

"I had a carb ice event last summer and would like to be pro -active on preventing another episode."

Best prevention is to;

Always apply carburettor heat BEFORE you reduce power.
Keep tabs on the weather forecast for humidity & temperature - apply your training - what are the chances of carb ice?

Best prevention is to;

Always apply carburettor heat BEFORE you reduce power.
Keep tabs on the weather forecast for humidity & temperature - apply your training - what are the chances of carb ice?

I once had what I think was carb icing while at cruise power. We were flying in humid conditions with some rain squalls around but not particularly low temperatures. The engine started to occasionally miss a beat accompanied by a sort of "bung" sound that could be felt as well as heard. When the misses became more frequent I turned back for our departure airport and increased the power slightly. The problem immediately stopped and has never recurred. We turned back to our destination and went on our merry way. I could find nothing wrong with the engine and the only cause I can think of is carb icing.

Peter

"Any reasons not to? "
"Cant see how it will help/inform you."


Having an alarm light blinking and informing you that your carb temp is currently in the temperature range where ice can form I think would be of great help.Doesn't mean that ice is forming but if moisture is present it's likely ,depending on the amount of moisture.Point being I now can monitor my rpm's closely ,or I could apply partial carb heat to raise temps until I see that it is above freezing.


I simply asked the question to discover if anyone had any problems/issues or concerns . Unlike many carburators that come with holes already drilled and tapped for temp probes the Zenith does not.
Cheers
Mike

Mike,
I don't know much about the Zenith except that it's a simple carb design like an antique Ford. I've seen a carb temperature gauge in a C182 before and it absolutely provides great safety margin because you can see if you are in the danger zone and control it with carb heat. So why not?

If you are drilling through it, take a look at all the factory drilled fuel passages to make sure you are not drilling through one of those. You can tell by the soldered in plugs at the ends of the passages. There are also a few tiny idle jet holes near where you want to drill.

Can you post a picture of the carb showing the brass plug you want to drill and tap? It could already be a plug from where the factory drilled a fuel passage.

Murray thanks I tried posting pics but no luck. here is a pic from the web and you can see the brass
plug near the bottom of pic.https://i.ebayimg.com/images/g/M0QAAOSw ... l1600.webp
That center plug is just above the idle mixture passages that open to the venturi and just above the butterfly in the upper throat of the venturi. The brass plug goes all the way through the body of the carb so I'm pretty sure there is no danger of cutting off a hidden passage.
Mike

Disclosure - Very limited experince, I have only known I had carburettor ice once, during preflight run up, in C172.

My training suggests that;

Ice rarely forms, when the engine is at or above crusie power.
Ice most likly to form after reducing power.
CHECK the weather & consult an icing probability chart BEFORE flight
ALLWAYS apply carburettor heat BEFORE reducing power
AVOID flight into cloud /mist (high moisture )

If you agree with /apply the above - how does a carburettor temperature gauge, inform the pilot any better than an OAT & a weather report?