Keeping Cool: Prestige Parts® Thermostats for Rolls-Royce and Bentley

Modern solutions are crucial for the maintenance and enhancement of classic vehicles and so Prestige Parts® uses computerised testing methods and upgraded thermostatic technology to manufacture thermostats that not only fit easily into your Rolls-Royce or Bentley but also ensure optimal cooling and performance under various driving conditions. 

All our thermostats operate on the same basic principle. Inside the thermostat, there's a container of wax that sits in the cooling system. As the temperature of your engine rises, the wax also heats up and begins to expand. This expansion exerts pressure on a pin inside the thermostat, which in turn opens a valve.

When the engine is cold, the wax inside the thermostat is not expanded. This means the valve is closed, effectively blocking the flow of coolant to the radiator. However, once the engine heats up and the wax expands, the valve opens to allow the coolant to flow through the radiator, cooling down the engine.

As the engine cools, the wax inside the thermostat contracts again, causing the valve to close. This cycle continues, over and over, allowing the thermostat to regulate the engine's temperature and maintain it at an optimal level.

The proper functioning of the thermostat is crucial in maintaining the perfect operating temperature, preventing overheating, and keeping your Rolls-Royce or Bentley running smoothly. 

While all thermostats operate in a similar fashion, different models and applications require specific fitments. Let's break it down:

RH9143: This thermostat fits six-cylinder cars such as Bentley Mark VI, R-Type, Rolls-Royce Silver Wraith, and Silver Dawn. It's a 78-degree thermostat and has been redesigned to fit the same housing as the later thermostat for S-Types and Silver Clouds.

UE30193: This 88-degree thermostat fits the V8 versions of Silver Cloud and S-Series Rolls-Royce and Bentley models, as well as Phantom V & VI limousines.if you are in a particularly hot country and you have a Silver Cloud you may wish to put a slightly lower rating thermostat in it so that it cools down earlier or vice versa. If your car is running cold then you may wish to put an 88 degree celcius thermostat in your Mark VI. These two thermostats are now interchangeable.

PG58252PA: This 88-degree thermostat fits Bentley S1 6-cylinder engine, V8 Bentley S2 and S3 models, Silver Shadow V8 range, the Silver Spirit, Turbo, and Arnage Red Label. This thermostat is an 88 degree celcius thermostat and it fits in the same place that thermostat UE36600 does.

UE36600: Similar to PG58252PA but with lead pellets for additional safety. These pellets act as a fail safe so that when it gets hot enough that if the thermostat were to fail and cause the engine to run too hot then it would actually melt away then these lead pellets would cause some flow through the radiator, and you would not get a complete shut-off of coolant. This thermostat is usually the preferred choice for the cars that fit this model.

UE366000-78: A 78-degree version of UE36600. It is not recommended for vehicles later than a Rolls-Royce Silver Shadow because those cars can be more sensitive with the running temperature.

PG100298PB: This is the original waxstat thermostat for the Bentley Arnage (08200 Onwards), Azure (11142 Onwards) & Brooklands Coupe (13501 Onwards). The earlier V8 thermostats have a paper gasket and the bolts for the housing are common to breaking just because there is a lot of corrosion around there and they can seize. This one seals on a little rubber lip around the thermostat and sits in the recess in the housing and there are 10 ml bolts which perform better.

PG29069PA: This unique design fits the Bentley Arnage Green Label, which is also a BMW design.

While the parts from the original Bentley factory may not be available or may lack modern technological advancements, Prestige Parts® steps in to fill that gap. Ready to upgrade the thermostat in your Rolls-Royce or Bentley? Our full range is shown here!

*Prices & Availability correct at time of publishing