Cam Angle (On Vehicle)

1971 GMC Jimmy 4.1L Eng VIN N, Automatic Trans, Trans Mfr CD THM350SECTION Cam Angle (On Vehicle)

With engine running at idle speed, lift window on side of distributor cap and insert a 1/8" Allen wrench into adjusting screw. Turn screw clockwise to increase cam angle and counterclockwise to decrease it. Use dwell meter to set cam angle to specifications.

If a dwell meter is not available proceed as follows: Turn adjusting screw clockwise until engine begins to misfire, then turn adjusting screw counterclockwise 1/2 turn. This will give approximate dwell angle required.

CAUTION: Use this method only when dwell meter is not available.
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.