Anyone out there using the cheapy HF compression tool? It does have the correct adaptor but it's not deep enough to work. Has anyone made and adaptor to fit down in the deep recesses of these Zetecs? OR bought one? OR had luck using the press in kind?
All I know is that you can often get away with cheap tools in replacement of better grade ones but compression testers are not one that rule fits. After using 2-3 sucky ones I bought expensive and no trouble since then. The cheaper ones often use crap relief valves that fake out your numbers bigtime, and fitment can be a problem as seen here.
Rule #1, NEVER use a press-to-seal type you are flat wasting your time, #2 always positively screw the o-ring sealed type up to seal right and take more than one reading ALWAYS.
Matched tools can help save a bit, even when higher priced.
Snap On may only be appropriate for pros, but their system is one to look for.
Flex adapter extensions fit both the compression gauge & the leak down tester. You only need to remove the Shraeder valve to use with the leak down tester. Air hose style quick connect fittings so you can screw in the adapter needed separate from attaching the gauge (saves on dinged gauges).
One caveat I learned for adapters using Shraeder valves - the "official" inserts are the ONLY ones to use. Tire valve inserts use a stronger spring & won't give results.