11/03/2026
Swapping parts until the problem goes away isn't troubleshooting. It's guessing, and guessing gets expensive.
In this clip from a recent Rogers Webinar, Eric Murray, Applications Engineer at MD-Kinney , emphasizes one of the first steps in diagnosing a vacuum pump issue: the blank-off test.
Close the isolation valve and see what vacuum the pump can actually achieve. Do this before replacing parts, throwing money at repairs, or changing the oil.
As Eric puts it: "I don't know how much more I can emphasize this. ALWAYS, ALWAYS, ALWAYS."
And if your system doesn't have an isolation valve? This is a pretty good reason to install one before you need it.