19. Install the degas bottle cap until it contacts the hard stop.
20. Turn the climate control system off.
21. Start the engine and increase the engine speed to 3, 500 rpm and hold for 30 seconds.
22. Turn the engine off for and wait for 1 minute to purge any large air pockets from the cooling system.
23.
WARNING: Always allow the engine to cool before opening the cooling system. Do not unscrew the coolant pressure relief cap when the engine is operating or the cooling system is hot. The cooling system is under pressure; steam and hot liquid can come out forcefully when the cap is loosened slightly. Failure to follow these instructions may result in serious personal injury.
Check the engine coolant level in degas bottle and if necessary fill to the top of the MAX FILL line on the degas bottle if the engine is warm or to the top of the MIN FILL LEVEL if the engine is cold.
24. Start the engine and let it idle until the engine reaches normal operating temperature and the thermostat is fully open. A fully open thermostat is verified by the cooling fan cycling on at least once.
25. Increase the engine speed to 3, 500 rpm and hold for 30 seconds.
26. Allow the engine to idle for 30 seconds.
27. Turn the engine off for 1 minute.
28. Repeat steps 25 through 27 a total of 5 times to remove any remaining air trapped in the system.
29.
Original technical text and illustrations, formatted as HTML. Follow the engine, transmission, equipment, model and year specified in the source. Import and layout checks do not establish applicability to every 2015–2017 Mustang. About this collection.