Cold start engine carburation system - has auxiliary air intake with suction and thermostat valves to regulate cold start fuel jet

摘要

The main induction pipe (1) has an auxiliary intake (4) joined downstream to the throttle valve (2). The auxiliary intake is open to atmosphere at the opposite end, and has an air filter. The auxiliary intake is additionally provided with a first regulator (5) which is suction-operated, and a second regulator (4) which is temperature-controlled. A fuel jet (7) is positioned preferably diametrically opposite the first regulator (5). The first regulator (5) consists of a spring-biased diaphragm (11) pressing a plunger (12) into the auxiliary air intake so that the air intake is throttled. The plunger end is tapered upwards to accelerate air flow. The diaphragm is connected to a vacuum pump (9). The second regulator unit (6) is a plunger (16) connected to a bimetal element (15), expanding to completely close the auxiliary air intake when the engine reaches working temperature.