1979 Jeep Wagoneer BaseFACTORY OEM SERVICE PROCEDURE

Single-Function for Standard Cooling

Connect a vacuum gauge to center port "D" of CTO switch. When coolant is below 160Β°F, manifold vacuum should register. Above 160Β°F, carburetor ported vacuum should be indicated. If valve does not respond, it must be replaced.

Factory Service Tools

Use the Manual With the Right Hardware

Pair factory procedures with proven DIY tools so the instructions are easier to execute.

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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.