They're used in cold weather ?Why do caps have nipplesView attachment 95024
And both cars (some models) used a gasoline fired burner heater drawing gasoline directly from the gas tank for fuel. Knew of them yet never even considered the potential danger ... if there was one. But they were rare since most cars of the day didn't have any heater at all.Fan on motor, you opened a shutter and heat directly from engine was, (Supposedly) ducted to the cabin. On the old VW’s you sometimes needed the ice scraper on the Inside. Good friend cut one of the ducts, wired in a 12v fan pulling (up front) and it would run you out. Also tons of fun if you had an exhaust leak or oil leak
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