Servo Diaphragm
- Check hoses for proper routing and condition. Start engine and set idle speed. Turn engine off, detach vacuum hose from servo diaphragm. Connect a vacuum hose directly from intake manifold vacuum to servo diaphragm.
Turn adjusting screw to obtain correct engine speed.
- Connect tachometer to engine. Start engine and let idle. Check for engine speed increase to 900-1100 RPM for Federal vehicles or to 1000-1200 RPM for California vehicles.
- If increase does not occur, adjust engine speed by turning adjusting screw on servo diaphragm throttle lever until proper speed is obtained. Reconnect all hoses to original position.