1. Open the tank cover. Make sure the tank is cooled before opening the cap.  2. Select the appropriate vehicle system water tank probe. 3. Insert the quick connector into the water tank probe. 4. Remove the hand pump set and pressurize until the gauge indicates about 15-20psi (or 1Bar). 5. Inspection pressure gauge: ● Assuming that the gauge pointer remains unchanged for several minutes, it indicates that the system is normal and can be used. ● If the pointer drops, it means that the system is cracked due to pressure damage. ● Check whether there is water leakage in each pipe of the water tank, and repair according to the location of water leakage. ● Check the condition of the rubber ring. ● Re-test to ensure that the repaired system is serviceable.  6. After the test is completed, return to 0 from the pressure relief valve to the pressure gauge.28pc Cooling System Pressure Tester & Vacuum Purge Master Kit Universal Radiator Pressure Test KitThe set is a all in one comprehensive radiator tool kit, includes leak detection, temperature measurement and coolant filling functions. The hand pump tester pressurize on the reservoir/cap, and watch for pointer drop over time to confirm system leak down. Vacuum filler first sucks and forms a vacuum on the cooling system by using shop air, then draws coolant into system. Add coolant in vacuum, there is no large air pocket and avoid warping or other damage in engine.Plastic covered premium brass manifold body, equipped with brass fittings, anti-corrosion and durable. The index range of gauge is -30 to 0inHg (-76 to 0cmHg), and normally -25 to -20inHg is right time to add coolant. 18" rubber resin material weave reinforced hose, featured with anti-corrosion, low fluid resistance, high bearing pressure, ensure durability and good air sealing. 21" metal hook, 23" transparent bleeder hose and 60" refill hose are included.