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1974 Midget

  1. Warm engine to normal operating temperature and remove air cleaners. Ensure carburetor piston dampers are filled to correct level with engine oil.
  2. Loosen clamping bolts on throttle spindle interconnections and disconnect jet control interconnection. Unscrew fast idle screws until they are clear of cams. Unscrew throttle adjusting screws until they are clear of stops and throttles are closed.
  3. Connect tachometer and exhaust gas analyzer to vehicle. Check idle speed and CO% level. To adjust idle speed, turn throttle adjusting screws until specified RPM is obtained. Turn each adjusting screw an equal amount.
  4. Use a carburetor synchronizer to ensure proper balance between carburetor throttle valves. Adjust each throttle valve adjusting screw so that an equal amount of air is passing through intakes.
  5. Turn jet adjusting nut on both carburetors up to lean mixture, down to richen mixture, until fastest idling speed is obtained. Turn each adjusting nut up (lean) until engine RPM just starts to drop, then turn both adjusting nuts one full turn down (rich).
  6. Gently tap neck of each carburetor suction chamber with screwdriver handle. Check that CO% level is set to specification. If not, reset both jet adjusting nuts by the minimum amount necessary to bring CO% level just within specifications.
  7. Hold jet adjusting nut on each carburetor to prevent it from turning. Rotate adjustment restrictor around nut until vertical tab contacts carburetor body on left-hand side, when viewed from air cleaner flange. Bend down small tab on adjustment restrictor. Tighten and/or reconnect components. Install air cleaners and recheck idle speed and CO% level.
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