Lisle LIS75500 Combustion Leak Detector Kit

Quickly pinpoints combustion leaks. Checks combustion leaks caused by bad head gaskets cracked blocks and cracked or warped heads. Indicating fluid changes from blue to yellow when exposed to combustion gases in the radiator. Connect the hose to any vehivle vacuum line. Place tapered end of tool into radiator opening after draining of some coolant. With the engine running the vehicle's vacuum draws vapors through the indicating fluid for testngIncludes leak detector and testing fluid.