What Causes Tire Slow Leaks?
2 Answers
Tire slow leaks are caused by: puncture by foreign objects; sidewall damage; aging or damaged valve stems. Puncture by foreign objects: Nails are the most common items that can puncture tires. Other items include screws, iron nails, wires, glass fragments, etc. These objects are very sharp and tiny. Once they puncture the tire, they can cause slow leaks, which are hard for car owners to notice. This situation is easy to resolve—just carefully inspect the tire surface for any foreign objects. Alternatively, if nothing is visible, sprinkling some water to see where bubbles emerge can also help locate the leak. Sidewall damage: When parking, it's easy to accidentally scrape the curb. Repeated scrapes can damage the tire sidewall, which is also prone to slow leaks. Additionally, this can lead to tire bulging and increase the risk of a blowout. Sidewall damage is relatively easy to spot, and if found, the tire should be replaced immediately. Valve stem aging: Valve stems are made of rubber, which tends to harden and crack over time, leading to slow air leakage from the tire.
Recently, my car's right rear tire keeps losing air, requiring inflation every two or three days. After taking it to the repair shop for inspection, I found out it was due to a slow leak. The mechanic sprayed soapy water and discovered a slight leak at the valve stem. Replacing the valve core fixed the issue. Actually, there are many reasons for slow tire leaks. The most common is a small nail puncture, but since the nail may block the hole, the leak is slow and hard to detect. Another cause is aging or cracking rubber on the valve stem, especially on tires that haven't been changed in seven or eight years. Wheel rim deformation is even more troublesome—last time, my friend's car scraped against a curb, causing slight rim deformation, which led to a slow leak due to poor tire-rim sealing. Additionally, cracks on the tire sidewall or rust on the rim edge can also cause air leaks due to poor sealing. Now, I always keep a portable tire pressure gauge handy and check the tire pressure weekly for peace of mind before driving.
