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Am I the only one who learned a better way to check for a vacuum pump leak in a Cessna 172 at a hangar in Daytona?

A guy there showed me to use a piece of rubber hose as a stethoscope on the pump case... you can hear the hiss way clearer than just feeling for air. What's your go-to trick for a quick vacuum system check?
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3 Comments
kai942
kai94224d ago
Daytona's a good spot for picking up tricks like that. Soapy water is solid, but what about those tiny leaks inside the pump itself that won't bubble? The hose trick might catch those sounds. Ever had a case where the soap didn't show anything but you still had a leak?
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clark.kelly
That hose trick is a solid idea for finding those internal leaks. @anderson.jason is right about soapy water being the first step for fittings and lines. I've also used a bright flashlight in a dark hangar to look for the tiniest oil mist spray from a leak, which can show up before bubbles form. Sometimes you need to try a couple methods to find the real source.
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anderson.jason
That hose trick is GENIUS. Honestly, the old "feel for air" method is pretty weak. My go-to is a simple soapy water spray on the pump and lines. Any leak, even a tiny one, blows a bubble you can't miss. Cheap, fast, and you don't need any special tools. Found a cracked fitting that way in under a minute.
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