[AJD] 1930 GP Leaky Radiator, Ensign Carb, Air Cleaner

[Spencer Yost]

>The carb feels cold when it is running.
> 

Yes, carburetors should feel cool, though how cool varies quite a bit
between carb designs and carb placement relative to the engine.  For those
on the list who don't know - maybe some of the younger folks who haven't
had much of a chance to work on carburetors, I'll explain(us older folks
need to remember we are in the days of fuel injection and "carburetor" is
an abstract term to most folks under 30).

Carburetors get cold because liquid gasoline requires energy to change to a
vapor state inside the carburetor.  This process grabs energy in the form
of whatever loose BTUs are hanging around venturi area of the carb.  It
gets some of these BTUs directly from the carb casting, but most of it
comes from the intake air stream.  However, then the air intake stream
sucks some BTUs from the carb casting, making it feel cool; and on
humid,cold days, making it ice up.  On cars where the carb was on top of
the engine and under a hood, icing wasn't as much of a problem.  However,
the updraft, side mounted and exposed-to-the-elements style carburetors
used on tractors would ice up more frequently.

Hope this helps,

Spencer Yost
Owner, ATIS
Plow the Net!
http://www.atis.net