To deflate a tire quickly for service or to replace a leaking valve, you need to remove the small spring-loaded valve core. A valve core tool features a slotted tip that fits over the shoulders of the core, allowing you to unscrew it from the valve stem. When removing a core, keep your face clear, as the air pressure will blast the core out of the stem like a projectile. Always install a new core when replacing tires or stems to prevent slow air leaks.
Mechanic Glossary
Valve Core Tool
A small screwdriver-like tool used to install and remove the valve cores inside tire valve stems.
Frequently Asked Questions
Overtightening will crush the delicate rubber seal on the core, causing it to leak air. Tighten it snug, but do not force it.
Yes. A/C service ports use Schrader valves that are similar to tire valve stems. You can use the same tool, but make sure the system is completely discharged first.
The valve core may be loose or contaminated with dirt. Try tightening it with the tool, or unscrew it and install a fresh core.