Service Precaution: Disconnecting and Reusing Ford “Spring Lock” Fittings
Ford uses a unique “spring lock” fitting on their air conditioning and fuel systems. The spring lock fitting is designed with an o-ring seal and spring tension to ensure a secure connection. Generally, the male end of the fitting has multiple o-rings and a round spring inside of a round housing. When fitted to the female end, the spring locks onto a lip, to create a secure connection.
When disconnecting lines with a spring lock fitting, it is important to use a spring lock fitting that is sized to that specific fitting to prevent damaging the internal spring. Spring lock fitting removal tools have a ridge that goes under the spring to expand and loosen tension so it can be easily removed. Pulling or using excessive force to remove spring lock fittings may break the spring or damage/bend the housing or lip.
When connecting lines with a reused spring lock fitting, it is highly recommended to replace the o-rings and internal spring. If an audible “click” is not heard when the male and female ends are connected, remove the male end and ensure spring is centered inside of the housing. To further ensure a secure seal, use mineral oil* to lubricate the o-rings.
*NEVER use PAG oil to lubricate o-ring seals. Because PAG oil is hygroscopic (absorbs moisture), it can lock the fitting in place, making it difficult to disconnect without damage