Thermal Vacuum Valve: Service and Repair

1. Drain coolant from radiator.
2. On V8 engines, remove air cleaner assembly.
3. Identify and tag vacuum hoses and disconnect from valve.
4. On six cylinder engines, place a suitable drain pan directly beneath CTO valve.
5. Remove valve from intake manifold or engine block on six cylinder engines, or from thermostat housing or intake manifold on V8 engines.
6. Reverse procedure to install.