SUBJECT--LEAN SURGE CONDITION 1955 V-8 CHEVROLET 
      CARBURETOR
      A lean surge condition, at speeds 
      ranging from 55-75 mph road load, has been reported on V-8 engines in the 
      field with both Powerglide and three-speed transmissions. This 
      condition will only be found where the Powerglide V-8 engine is equipped 
      with carburetor part No. 7005810 or where a three-speed transmission V-8 
      engine is equipped with carburetor part No. 7006825. The condition may be 
      corrected by replacing the venturi 
      cluster assembly and The main metering jets in the carburetors.
      On Powerglide V-8 carburetors, 
      venturi cluster part No. 7007989 replaces cluster assembly No. 7000287 and 
      main metering jets (two) part No. 7002951 replace main jets part No. 
      7002952. On the three-speed transmission V-8 engine carburetor the venturi 
      cluster assembly part No. 7007990 replaces cluster assembly No. 7006844 
      and main metering jets (two) part No. 7002952 replace main jets part No. 
      7002953.
      Carburetor, part No. 7008004. 
      used on the Powerglide V-8 engine, and carburetor part No. 7008005, 
      used on the three-speed V-8 engine, have the new venturi cluster 
      assemblies and main metering jets and are not subject to- the lean surge 
      condition.
      Policy: This modification is to be handled on a maintenance 
      basis.
      (0467 PD 3-55)        
                          
          -0-                  
                (Printed in U. S. A. 
      )
      AA, GO:9, WD, 131, 
      132:9-13