Sounds like what the old Lycoming engines experiance in the airplane world. They typically have a lever in the cockpit to pull for carb icing. Typically re-directing some exhaust manifold heat to the carb area, to clear the obstruction....
Probably came about as it was hard to pee on the carb while in flight...


1958 Chevy Apache Fleetside/235/3 sp
Pictures at http://www.facebook.com/album.php?aid=317454&id=855355703&l=0a0f773195