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Home >> Oldsmobile >> 1963 >> Dynamic Base, Eng CD JS, Automatic Trans >> Repair and Diagnosis >> Engine Performance >> Fuel Delivery >> ROCHESTER 4GC 4-Barrel >> Overhaul >> Disassembly >> Throttle Body
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Throttle Body

Invert carburetor and remove fast idle cam and choke rod, idle mixture screws and springs, idle air by-pass screw and spring, and vacuum hose fitting. Remove throttle body-to-main body attaching screws (one large screw and lockwasher located in counterbore in center of throttle body - see Fig 1); lift throttle body off. Remove secondary auxiliary throttle valve assembly from lower side of main body

Fig 1: BOWL COVER SCREW LOCATION & TIGHTENING SEQUENCE
G09353196Courtesy of GENERAL MOTORS COMPANY
Fig 2: AUXILIARY THROTTLE VALVE INSTALLATION
G09353197Courtesy of GENERAL MOTORS COMPANY
Fig 3: ROCHESTER 4GC 4-BARREL CARBURETOR ASSEMBLY (TYPICAL)
G09353198Courtesy of GENERAL MOTORS COMPANY
CAUTION: (Do not attempt to disassembly auxiliary throttle valves; valve spring tension is calibrated and setting will be lost if assembly disturbed).

This completes throttle body disassembly. Do not disassemble throttle levers or remove throttle valves (throttle body is serviced as an assembly with throttle valves, levers, and linkage).