Bentley Bentayga Continental GT Flying Spur W12 Thermostat Housing Assembly 07P121115J – 104°C Coolant Regulator

Bentley W12 Thermostat Housing Assembly – 07P121115J

This complete coolant thermostat / regulator housing assembly is engineered for Bentley W12 cooling systems using OE reference 07P121115J. It is a high-value replacement for the thermostat module fitted to selected Bentley Bentayga, Continental GT and Flying Spur 6.0 W12 applications. The thermostat controls coolant routing as the engine warms, helping the W12 reach and maintain its designed operating temperature efficiently.

Materials & Engineering

The assembly is built around a robust cast-metal coolant housing with accurately formed hose connections, machined sealing faces and an integrated thermostat mechanism. Its multi-port layout is designed to manage the high coolant flow requirements of Bentley's W12 engine. Equivalent thermostat specifications for 07P121115J use a 104°C opening temperature, supporting controlled warm-up and stable thermal management.

Why the Thermostat Matters

• Regulates coolant flow between the engine and radiator circuit.
• Promotes faster controlled warm-up from cold.
• Helps prevent persistent overcooling caused by a thermostat stuck open.
• Helps restore correct circulation when an old thermostat sticks or the housing leaks.
• Supports consistent heater output and stable engine temperature.

Fitment

Designed for Bentley vehicles using part number 07P121115J, including compatible W12 versions of the Bentayga, Continental GT and Flying Spur. Match the existing part number or vehicle parts catalogue before purchase.

Replacement Guide

1. Allow the engine to cool completely and release cooling-system pressure safely.
2. Drain the coolant to a clean container and remove the necessary intake covers or ducts for access.
3. Mark hose positions, release the coolant-hose connections and disconnect any attached electrical connector.
4. Remove the thermostat-housing fasteners and lift the old assembly away.
5. Clean the mating surfaces and install fresh seals or O-rings used by the cooling circuit.
6. Install the 07P121115J assembly, tighten fasteners evenly and reconnect all hoses.
7. Refill with the correct Bentley/VAG-spec coolant mixture, bleed trapped air and bring the engine to operating temperature.
8. Check all joints for leaks and verify stable coolant temperature.

FAQ

What symptoms can a failing thermostat cause?
Common symptoms include slow warm-up, unstable temperature, overheating, coolant leakage around the housing and reduced cabin-heater performance.

Is 07P121115J a thermostat only or a housing assembly?
This listing is for the complete thermostat/regulator housing assembly shown in the product images.

What is the reference opening temperature?
Equivalent 07P121115J thermostat specifications use a 104°C opening temperature.

Should coolant be replaced during installation?
Fresh correct-spec coolant is recommended whenever the system is drained for a major cooling-system component replacement.

How do I select the correct version?
Use the exact OE reference 07P121115J and confirm the same number on the original assembly or parts catalogue.