OE Aftermarket 12A1139 Cork Side Cover Tappet Inspection Gasket

The OE Aftermarket 12A1139 is a cork side cover gasket designed for BMC Leyland B-series 1.5L and 1.8L engines. This thin cork gasket seals the tappet inspection plate on the side of the engine block, preventing oil leaks and protecting critical valve train components.

Key Features:

• Cork construction provides reliable sealing and compression resistance
• Direct replacement for OEM part number 12A1139
• Designed for flat flange side covers on early BMC engines
• Compatible with 998cc, 984cc, and 1098cc engine variants
• Also known as tappet chest gasket or side cover inspection plate gasket

This gasket is commonly found on classic British vehicles including Mini Cooper S, MG MGA, MG MGB, Morris Minor, and marine applications such as Leyland Thornycroft 90, Thornycroft 108, and Newage Captain 1.5 boat engines. Cork material ensures proper oil sealing while allowing for minor surface imperfections on vintage engine blocks.

Cross References: CKS809, 12A1139B