Testing The Cooling System

TOOLS REQUIRED : Cooling System Pressure Test Adapter (J43421).

WARNING: Do not remove the cap from a hot system. Allow the system to cool, then slowly remove cap.

Remove the pressure cap from the coolant surge tank.
Make sure that all the parts of the cap, tester, and adapter are clean.
Install cooling system pressure test adapter to coolant surge tank.

Fig 1: Installing Cooling System Pressure Test Adapter
Courtesy of GENERAL MOTORS CORP.

WARNING: Wear safety goggles.

WARNING: Never pump the system above 138 kPa (20 psi).
Pump the tester until the gauge needle reaches 138 kPa (20 psi).
Watch to see if needle falls. Inspect all hoses for excessive swelling. Check all joints for leaks.