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Single-Function For Standard Cooling (6 and 8 Cylinder)

Connect a vacuum gauge to center port "D" of CTO switch. When coolant is below 165°F, manifold vacuum should register. Above 165°F, carburetor ported vacuum should register. If valve does not meet these requirements, it must be replaced.

Fig 1: Vacuum Spark Control Delay Valve (4 Cylinder Engines)
G09337304Courtesy of CHRYSLER GROUP, LLC
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