Four Seasons 26776 A/C System Valve Core and Cap Kit

AC System Seal Kit for R12 and R134a

Restore service-port sealing and valve-core retention with the Four Seasons AC System Seal Kit, part number 26776. This cap and valve A/C system seal kit is built for R12 and R134a refrigerant service and is used on a wide range of GM cars, trucks, and vans from 1987-1993.

Four Seasons AC System Seal Kit 26776 is a practical replacement for worn, cracked, or missing A/C service caps and valve-core seals on applications such as Buick Century, Chevrolet Camaro, and GMC C1500 models.

Key Features

• Part number 26776 from Four Seasons AC System Seal Kit line
• Cap and valve kit style for A/C service-port sealing
• Works with R12 and R134a refrigerant systems
• Plastic caps in red, blue, and black
• Aluminum construction for the seal kit components
• Fits a broad range of 1987-1993 GM HVAC applications

Product Details

The Four Seasons AC System Seal Kit line focuses on service-port sealing components for automotive air conditioning systems. This kit combines cap and valve-core sealing elements in a cap-and-valve format, helping maintain a secure seal at the A/C service ports during routine maintenance or retrofit work. It is listed for many GM platforms, including Buick, Cadillac, Chevrolet, GMC, Oldsmobile, and Pontiac vehicles across the 1987-1993 model years.

Fitment includes applications such as Fits 1991-1993 Buick Century, N/A; Fits 1988-1993 Chevrolet Astro, N/A; and Fits 1989-1993 GMC C1500, N/A. This part cross-references Global Parts Distributors LLC 1311423 for the same application.

Common Uses

• Replaces damaged or missing A/C service-port caps
• Addresses refrigerant leakage at valve-core service points
• Helps correct poor sealing after A/C maintenance
• Supports retrofit service on select R12-to-R134a applications
• Restores proper protection for exposed service ports

Installation Notes

Verify refrigerant type, service-port style, and vehicle fitment before installation. Confirm the cap inside diameter and valve-core style against the existing A/C hardware, especially on retrofit-equipped vehicles. Clean the service-port area before installing the new cap and valve components to help ensure a proper seal.

Quality Assurance

Four Seasons supplies HVAC service components for automotive air conditioning repair and maintenance. Part number 26776 is cataloged for direct application matching across the listed GM vehicles and refrigerant types.