The 7 Best Leak Down Testers
Editor's Notes
February 19, 2020:
If you're trying to decide whether or not to condemn an engine, the last thing you want to settle on is the quality of your leak down tester. Any tool that does not come with gauges to measure both pressure and leakage has been omitted. In some scenarios, an engine may create an acceptable amount of compression but worn-out piston rings or valves could be allowing pressure to escape. Keep in mind that when a fitting size is listed, you should have your vehicle specifications handy and check compatibility before purchasing.
This Wiki includes options for daily, rigorous professional use like the OTC 5609, as well as others for the odd job at home in your garage like the Faersi Cylinder Leak Detector. The Lang Tools CLT-2 is a worthy contender if certain professional brands are out of your budget.
Each tester comes in a durable case except for the Innova 3612, chosen for its versatility of application and caliber. One common problem with many of the leak-down testers is the quality of the fittings. Some are poorly machined and won't thread well. Others may not be clamped on to the hose and allow air to escape during a test, thereby causing a false reading. These types of scenarios are accounted for in our ranking process to ensure every option is truly the "best of."
Unintentional damage can be caused if performing a compression test incorrectly and should not be attempted without technical training.