If you’ve ever built an engine, taken apart an old jet ski for parts, or had to troubleshoot an engine for any reason, there’s a good chance you know the importance of pressure testing. However, if it’s your first time around, you’re in luck! The good people over at Erickson Machine and Performance have produced a detailed guide to this essential aspect of engine maintenance. Their video details the ins and outs of pressure testing a 2-stroke engine, using the custom-built ET 967 as an example.
In the video, Mark stresses the importance of pressure testing in a variety of scenarios. First and foremost, he emphasizes that it is imperative whenever one is assembling a new engine, so as to avoid significant issues in the PWC’s performance. Furthermore, it is an important step in diagnosing an older engine, especially if it is being used in a new build or if it seems to be running lean.
Before beginning the test, Mark highlights a few crucial preparatory steps. For Yamaha skis, it’s important to pull the starter or pop the front cover. For Kawasaki, you need to open up the inspection port. Both of these steps prevent pressure from being trapped due to leaking front seals, which could result in a buildup of oil over time, along with other potential issues.
In the video, Mark also goes through the necessary tools, including homemade options and available-to-purchase kits, to perform the pressure test. These include block off plates, rubber valves, and the air-regulating tool (the video goes into detail about how to build these from pieces you may already have).
The testing procedure itself involves gradually increasing the pressure to 8psi, then leaving it for 2-3 minutes to see if there is any leakage measured by the air regulator. If there is none, you should be good to go!
Check out the full video to see the detailed procedure, and check out the Erickson Machine and Performance channel for a wide variety of technical walkthroughs and resources.
