Performance Water Pump & Thermostat Kit for Jaguar XJ (2010-2019) 5.0L

Heavy-Duty Water Pump & Thermostat Cooling Overhaul Kit for 2010-2019 Jaguar XJ (X351)

What it Does: The Performance Water Pump and Thermostat Kit replaces brittle factory cooling components on the 2010-2019 Jaguar XJ to prevent catastrophic coolant loss and maintain critical thermal regulation under boost.

The Stock Jaguar XJ Cooling System Weakness

The factory cooling circuit on the X351 chassis relies on multi-piece molded plastic coolant crossover tubes, plastic thermostat housings, and composite bleeder plugs. Under the intense thermal cycling and under-hood heat soak generated by the supercharged AJ133 V8, these nylon-composite pipes become brittle, heat-cycle fatigue, and crack along ultrasonic weld seams. When these plastic pipes fracture, rapid coolant depressurization can cause sudden head gasket failure and cylinder head warping before dash sensors register overheating.

The Engineering Solution

This comprehensive cooling package replaces the notorious OEM failure points with structural aluminum coolant crossover pipes and reinforced copper fittings that withstand continuous elevated operating pressures and high-temperature thermal cycling. The included heavy-duty mechanical water pump features an upgraded bearing pack and shaft seal to mitigate cavitation at high engine RPM. Paired with a pre-assembled thermostat unit featuring an integrated coolant temperature sensor and a solid copper bleeder screw, this direct-replacement kit eliminates weak failure-prone plastic junctions entirely.

What's Included

• 1x High-Flow Mechanical Water Pump
• 1x Thermostat Assembly with Integrated Sensor
• 1x Aluminum Coolant Crossover Pipe Assembly
• 1x Thermostat Outlet Hose with Copper Fittings
• 1x Copper Bleeder Screw & Crossover Plug
• 1x Heater Outlet Hose

Technical Specifications

Compatibility

• 2010-2019 Jaguar XJ Supercharged (5.0L Supercharged V8)
• 2010-2019 Jaguar XJ Supersport / XJR / XJR575 (5.0L Supercharged V8)
• 2013-2019 Jaguar XJ 3.0L Supercharged V6 (AJ126 Engine Platform)

Frequently Asked Questions & Fitment Warnings

Does this fit the X351 XJ?

Yes, this is a direct fit for the 2010-2019 Jaguar XJ equipped with the AJ133 supercharged engine. Does not fit naturally aspirated 5.0L V8 models.

Do I need to bleed the cooling circuit after installation?

Yes, the supercharged cooling system requires a full vacuum evacuation and coolant bleed using the included copper bleeder screw to eliminate air pockets around the supercharger charge coolers.

The Jaguar European Standard

Precision-engineered to meet European tight-tolerance cooling specifications, this aluminum-upgraded cooling system preserves factory sensor calibration without throwing check engine lights while securing your high-displacement powertrain from catastrophic thermal breakdown.