On 12/7/2010 6:41 AM, Larry Alofs wrote: > It has been my impression that the accelerator pump in a carbureted > system is, in part, designed to cope with the loss of vacuum when the > driver steps on the gas suddenly. Less vacuum means less gas being > sucked thru the jets. > > Larry A. Larry, you are exactly correct - almost. When one puts the pedal to the metal, the opening of the butterfly valve in the carburetor throat permits more air through it. In that moment of time, there is a lag in fuel flow and with increased air flowing through the carburetor the fuel mixture suddenly goes lean, even to the point of stalling the engine. To compensate for this, the engineers have added a device called an accelerator pump. It is designed to give a squirt of raw fuel directly into the throat of the carburetor thereby giving an additional charge of fuel to the mixture so as to prevent the stalling of the engine when the butterfly opens suddenly. Just my $0.02. Regards, John .
John Rodgers Clayartist and Moldmaker 88'GL VW Bus Driver Chelsea, AL Http://www.moldhaus.com |
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