Gates 31550 Radiator Cap

OE Type Radiator Cap for Jaguar Cooling Systems

The Gates 31550 OE Type Radiator Cap is built for closed coolant recovery systems that require accurate pressure control and a threaded coolant bottle cap design. It is engineered to meet OE performance expectations for select Jaguar applications, including Jaguar X-Type, XK8, XKR, XJ8, Vanden Plas, and XJR models.

Gates OE Type Radiator Caps are made with corrosion-resistant metal or high-quality plastic, depending on application, to support long service life and consistent sealing performance. The 31550 is rated at 15 psi and is designed to match OEM specifications in function, form, and fit.

Key Features

• Gates part number 31550
• OE Type Radiator Cap for closed coolant recovery systems
• Threaded coolant bottle cap design
• 15 psi pressure rating with SAE pressure range of 14-18 psi
• Filler neck inside diameter: 1.5 in. / 38 mm
• Filler neck outside diameter: 2.07 in. / 53 mm
• Filler neck depth: 1.25 in. / 32 mm
• Shell diameter: 2.46 in.
• OE Performance rating

Product Details

The Gates 31550 radiator cap is a direct-fit cooling system service part for vehicles that use a threaded coolant bottle cap and a 15 psi pressure specification. It helps maintain proper system pressure, which is important for stable coolant operation and reliable radiator performance. This part cross-references Dorman - HELP (e.g., 46081) for the same application.

Compatible With 2001-2007 Jaguar X-Type, N/A; 1997-2006 Jaguar XK8, N/A; 2000-2006 Jaguar XKR, N/A; 2005 Jaguar XJ8, N/A; 1998-2003 Jaguar XJ8, N/A; 1998-2003 Jaguar Vanden Plas, N/A; and 1998-2001 Jaguar XJR, N/A. The Gates 31550 is also listed for Jaguar cooling system service where OE-style pressure control is required.

Common Cooling System Issues It Can Address

• Loss of coolant system pressure from a worn or weak cap
• Coolant overflow or recovery issues in a closed system
• Improper sealing at the filler neck
• Pressure-related cooling performance concerns
• Replacement of a damaged or corroded radiator cap

Installation Notes and Tips

Verify the filler neck dimensions, depth, and pressure rating before installation. This cap is specified for a closed coolant recovery system and a threaded coolant bottle neck, so matching the application details is important for proper sealing and pressure control. Inspect the neck surface for damage or debris before installing the cap.

Quality Assurance

Gates manufactures this OE Type Radiator Cap to meet or exceed OEM specifications in function, form, and fit. The construction uses corrosion-resistant materials selected for the application, and the design is intended to support accurate pressure control and long service life.