The performance tool w89729 leak down test kit can quickly diagnose internal engine problems such as bad rings valves and leaking head gaskets. An engine leakdown test is a compression test in reverse.
Anyone Modified A Leak Down Tester For Diagnosing A Cylinder
Diesel leak down test. Leak down tests on diesels in aircraft the leak down test is used because you dont want to stand next to a spinning prop doing a compression test. Disable fuel injection by pulling the fuel. In the leak down test you move the up to tdc because of cylinder choke then work the prop back and forth to seat the rings. The crankshaft is then turned so that each piston is at top dead centre. Unlike a compression test a leak down tester has two gauges and requires a compressed air source. The tester then measures the volume of air needed to maintain a predetermined pressure in the cylinder.
A cylinder leak down test requires the removal of all the spark plugs. Compressed air 80 to 90 psi is then fed into the cylinder. One gauge on the tester measures the pressure of the air entering the cylinder and the other measures the percentage of the air escaping or leaking from the cylinder. Test the engine at operating temperature for the best results. A threaded coupling is screwed into a spark plug hole. In a cylinder leak down test the engine is placed on tdc of the cylinder in question.
This cylinder leak down tester gauges leak down tests more accurately than standard compression tests. Then using a similar type of connector as the compression test we fill the cylinder with pressure. Unplug the coil wire from the distributor to prevent the engine from firing while testing. Like a compression test a leak down test is accomplished by replacing a spark plug with the tester hose. Instead of measuring the engines ability to create pressure compressed air is introduced into the cylinder through the spark plug hole. 10 millimeters and 14 millimeters thread adapters dual 2 12 inch chrome bezel gauges and rugged protective outer shell pressure regulated manifold with quick couplers and all comes with an easy to open blow molded hard case for storage.
Pressurized air is supplied to each cylinder and in moments displays a rate of leakage measure from 0 to 100. Leak down is the percentage of compression that is lost by the engine and every engine has some.


















