Chill from the past
 

My son and I just got home from the PCA meeting. It's 37° and foggy / drizzly.

We were barely home and my son told me the neighbor kid (20) wanted me to come over and check his Beetle (74 Super Beetle).

My neighbor passed away last year. His sons are friends with my sons and I've long been a consultant on auto issues. They have an E30 as well as the Beetle.

We get over there and the beetle is idling rough, with the lid open. The owner asks " what is that stuff on my carb and why is it running bad?"

Carburetor Icing! I haven't seen that in over a decade!

wow, I've never seen that or heard of it. But then I've not spent that much time up North either.

This temperature (just above freezing) and near 100% humidity, plus a carb that has no heating provisions and that's what you get.

As the air accelerates through the venturi the temperature drops.

Icing on the cake - the throttle was sticking open as he drove it home.

I love these young guys working with the old cars ( they still have 2 65 Galaxie convertibles that were their dad's).

that situation gets serious in an aircraft.

I had carb icing in an old 83 Ford pickup with a 300CI inline 6. Somebody had removed all the "junk" around the carb when they rebuilt the motor.

That takes me back to the 1960's when I was working on the surface of a mine in Elsa, Yukon. This ex Englishman there had a Mini Cooper S(1275cc) and said he experienced carb icing that I thought only in retrospect piston engine aircraft experienced.

I forgot about that and I have never had any car in my life experience that.
It is indeed great that you can help out others with their cars especially the young ones.:)
Cheers, Guy.

If it's bad and you have to make it home take a pee on the carb.

Not joking. SmileWavy

in the winter we used to zip tie a piece of plexiglass over the engine lid louvers to keep the heat in. helped a lot.

Back when I was 15 I helped my brother build a dune buggy from a VW. The engine just hung out in the air. Down in Alabama on a cool day while driving around it started running real bad. We pulled over and the carb was a block of ice.

We hooked up a new preheat manifold after that weekend.

The carb iced up once on me in the '73 Torino under the conditions described above.
It was like trying to run with full choke. No power, black smoke from the exhaust. :(
We limped into the next town and a couple of bottles of gas line de-icer and the heat from the engine cleared it.

Best
Les

my 76 FJ40 with a Holley 2 barrel conversion, it would ice up when it was cold out,
the trick was to keep it running long enough to get some heat into the engine,
usually about 10 mins then shut if off,
and let the carb warm up usually about 5 more mins
otherwise you could find the throttle stuck at way more than idle

This is why there's carb. heat (or injection). Anyone who's flown an older C172 will know it well as part of their basic procedures. I still have it burned into my head from the first plane I ever soloed (a PA28) as part of the engine power loss troubleshooting procedure, "mixture rich, fuel pump on, carb heat on, switch tanks". Would be simple enough to rig up on a car I'd think - one cable, a butterfly valve, two metal flex hoses and a few clamps...

Back in the day....When I was flying "round engine" aircraft, carburator icing could occure at +15C and below. Carb heat is term now that only flyers of small piston driven aircraft are familiar with.