Which liquid is commonly used to check for leaks in fuel systems?

In fuel system maintenance, a soapy water solution is commonly used to check for leaks because it provides a simple and effective method for identifying escaping gases or liquids. When applied to suspected leak areas, the bubbles formed by this solution will accumulate at the leak points, making it easy to detect even small leaks.

The composition of the soapy water allows for excellent surface tension, which ensures that the bubbles form and persist long enough to be observed, enhancing the leak detection process. This method is also relatively safe and non-intrusive, making it ideal for various applications in fuel systems maintenance.

While water alone lacks the capability to produce bubbles that clearly indicate a leak, and other liquids like mineral oil or alcohol may not adhere well enough or produce visual indicators of leaks, the soapy water solution proves to be the most suitable choice for efficient and straightforward leak detection.