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Manuals through 2025 now available!

Our trusted friends have launched a new website named LEMON, which has newer manuals. It also contains all the CHARM manuals.

LEMON is the spiritual successor to CHARM, I recommend you try it!

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Idle Speed/Throttle Actuator - Mechanical: Description and Operation

Fig. 24 Vacuum operated throttle modulator (VOTM):





The VOTM, Fig. 24, acts as a variable carburetor stop. The plunger extends when vacuum is applied.