Radiator Expansion Tank Cap Test
  1. Remove the expansion tank cap (A), wet the seal with engine coolant, then install it on the pressure tester (B) (commercially available). Use a small adapter KE-30-5 (C) (commercially available) to install the expansion tank cap.
  1. Apply a pressure of 112−146 kPa (1.14−1.49 kgf/cm 2 , 16−21 psi).
  1. Check for a drop in pressure.
  1. If the pressure drops, replace the cap.