Expansion tank cap check

Caution: To avoid burns, do not remove the radiator or expansion tank cap while the engine is hot.

1. Remove the radiator cap.

2. Rinse the sealing surface of the cover with clean water.

3. Install the cover on the cooling system tester.



4. Pressurize the cap and check the pressure to start depressurizing. Compare with lid valve opening pressure rating (marked on the cover). Estimate the rate of pressure drop.

5. Replace cap if:

• the opening pressure of the lid valve is greater than the nominal pressure.
• cap does not hold nominal pressure for 10 seconds.