Temperature-Controlled Idle Speed Boost

The temperature controlled idle speed boost is operated by a temperature-dependent control. In a cold engine condition the speed adjusting lever will be on the knurled stop plate and not on the idle speed adjusting screw. This will boost the idle speed and improve the warm-up phase of the engine. When the engine is warm, an expanding material element will release the speed adjusting lever so that it now rests on the idle stop screw and the temperature-contolled idle speed boost is no longer effective.