Fix A Leaking Tire Valve Stem In 5 Minutes - The Family Handyman

Diagnose and fix a leaky valve stem

You topped off the air in your tires, but a few days later, you notice that one of them is low again. It could be a hole, but before you go through the hassle of searching for one or making an appointment at the tire shop, first check for a leaky valve stem.

“Leaking tire valve stems are common, leading to air loss over time,” says Duane “Doc” Watson, a technical trainer at Bosch Mobility Aftermarket. “Age, weather exposure and regular use can all lead to them leaking.”

If the valve stem is your culprit, you can probably fix it yourself with a valve stem tool (aka valve core tool) and a package of new valve stem cores, both of which are inexpensive and relatively easy to use. Here’s how.

How to diagnose a leaky valve stem?

To determine if the valve stem is the cause of your deflating woes, remove the cap. “If you hear or feel air rush out, if the cap is cracked or if the stem bubbles when you put soapy water on it, all are signs of a leaking valve stem,” says Chris “Moose” Pyle, an auto repair expert at JustAnswer.com.

Check and remove the valve stem

Use your valve stem tool to check the tightness of the valve stem. If it wasn’t tight, then tightening it and adding a little more air into your tire might be all you have to do. If it is tight, use the tool to pull out the stem (wearing safety glasses to protect your eye from any debris that might ensue).

“When you remove the stem, all the air is going to come rushing out, and the stem may shoot across the driveway,” says Pyle. “So hold it tight and do realize you need a way to refill the tire with air.”

Squirt soapy water into the tire valve stem. If you see bubbles form, you have a slow leak. We’ll show you how to fix a tire leak.

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Car Maintenance: Make Your Tires Last