Lifter Adjustment (Engine Running)

1966 Chevrolet Chevelle Base, Not Available, 6.5L Eng, Standard Trans, Trans Mfr CD SM326SECTION Lifter Adjustment (Engine Running)

With engine warm and idling, back off rocker arm stud adjusting nut until rocker arm starts to clatter against valve stem, then turn nut down until clatter just stops. This is "Zero Lash". Now turn nut an additional 1/4-turn and wait until engine runs smoothly. Continue to turn nut down in 1/4-turn increments until nut has been turned down 1 full turn from "Zero Lash".

CAUTION: Make adjustment slowly so lifter will adjust itself and prevent engine damage.
SPARK PLUGS

Gap (All) .035" (.033-.038")
Torque (All) 20-25 Ft. Lbs.
Spark Plug Type

Standard (All) AC 46N
Colder (All) AC 44N
RENDER: 1.0x

NO RELATED

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • β€’ You smell fuel, burning insulation, or see smoke.
  • β€’ Brakes feel soft, pull hard to one side, or make grinding noises.
  • β€’ The engine overheats, stalls repeatedly, or misfires under load.
  • β€’ You are missing required tools, torque specs, or safe lifting equipment.
  • β€’ You are not confident in the next step or safety outcome.