Air Valve Spring

1973 Chevrolet Caprice Estate, Not Available, 5.7L Eng VIN HSECTION Air Valve Spring

To adjust air valve spring wind-up, loosen lockscrew (Allen screw) and turn adjusting screw counterclockwise to remove all spring tension. With air valve held closed, turn adjusting screw clockwise until torsion spring just contacts pin in shaft; then turn adjusting screw clockwise as specified in following table. While holding adjusting screw in this position, tighten lockscrew.

Fig 1: AIR VALVE SPRING ADJUSTMENT
G09340933Courtesy of GENERAL MOTORS COMPANY
Application Amount of Turn
Buick
  455" 7/16"
  350" 11/16"
Cadillac
  Except Eldorado 5/16
  Eldorado 3/8
Chevrolet
  350" 1/2
  350" (1) 3/4
  454" 11/16
Oldsmobile
  350" 1/2
  455" 3/4
Pontiac
  7043263 5/8
  7043264 1/2
  7043274 9/16
  7043262 3/8
  7043265 9/16
  7043272 3/8
(1) Z-28 & Corvette with 9.0:1 compression ratio.
RENDER: 1.0x

NO RELATED

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