Operation CHARM: Car repair manuals for everyone.
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!

Link: lemon-manuals.la or lemon-manuals.org.ua

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Altitude Compensator: Testing and Inspection




1. Remove air cleaner and start engine. Engine should idle smoothly.
2. Position finger over slow port in carburetor air horn and observe idle speed. Idle speed should drop. If idle speed does not drop, proceed to next step.
3. Remove altitude compensator valve from carburetor, then blow air through passages. Air should pass through valve in both direction. If air does not flow as indicated, replace altitude compensator valve.

NOTE: The operation of the altitude compensator valve should be checked at altitudes of 1640-4920 feet because operating specifications of valve will change at lower altitudes.