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Ignition System - HEI/Est/ESC: Overhaul

CAUTION: Although similar in appearance, components of HEI/EST and HEI distributors are NOT interchangeable.

Ensure pick-up assembly arm is correctly installed on pin. If not, arm can float and cause ignition timing to vary. To prevent corrosion, ensure module terminals are lubricated with petroleum jelly before installation. To prevent heat damage, coat bottom of module and module rest pad in housing with silicone grease. Before installation of roll pin in driven gear, ensure timing mark on roll pin and rotor tip align. See:

Fig 1: Exploded View of HEI-EST Distributor With Sealed Connectors
G16032Courtesy of GENERAL MOTORS CORP.
Fig 2: Exploded View of HEI Distributor
G72865Courtesy of GENERAL MOTORS CORP.
Fig 3: Exploded View of HEI/EST Distributor With Hall Effect
G16033Courtesy of GENERAL MOTORS CORP.