A retaining system for a solenoid assembly of a liquid adhesive dispensing system includes a quick-release mechanism configured to secure the solenoid assembly in place. The quick-release mechanism engages an air tube of the solenoid and thereby secures the entire solenoid assembly to a manifold. The quick-release mechanism can release the solenoid, facilitating easy removal of the entire solenoid assembly, by a simple turning, pushing, or pulling action on the quick-release mechanism. The released solenoid can then be removed and replaced, thereby minimizing downtime caused due to the replacement of a faulty solenoid.