Fast, economical and accurate method to test for combustion gas leaksWorks onPetrol, DieselandLPGenginesSure diagnosis within a few minutesPositive proof that a leak is present when the tester fluid changes colour on detection of CO gas - if there is a hairline crack in the cylinder head, engine block or damage to the cylinder head gasket, the test fluid turns yellow.Ideal for routine checks and scheduled maintenance workIdeal for engine checks on used carsSpecifications: Material: Polypropylene Size : 5.5*17CM Color: White Type: Head Gasket & Block Tester KIT How does it work? In the case of a damaged gasket under the head or the head itself, part of the combustion gases containing COgoes to the cooling system, at this point they react with the liquid and change its colour. Performing the test: 1.Fill the device with reaction fluid to the level just below the chambers (approx. 2ml), as shown in the photo below. 2.Connect the tester to the opening of the expansion tank or radiator. 3.Start the engine (preferably already warm), bring it to a higher speed to obtain a higher combustion pressure. 4.Let the engine run at a slightly increased speed and observe the behaviour of the reaction fluid. 5.Changing the colour of the reaction fluid to yellow within a few minutes indicates a damaged gasket under the head or damage to the head itself. 6.After the test has been completed, carefully remove the device. The used test fluid should be disposed of, even if the test result was negative. (We would never recommend using any combustion leak detector fluid twice, as this may affect the accuracy of the test). Package Included: 1X combustion leak detector(Fluidnot included)