Radiator, Water Pump & Thermostat Repairs in Sunbury-on-Thames
The radiator, water pump and thermostat do most of the cooling system’s work. When one fails, the symptoms often overlap, so confirming which part is at fault saves money.
We diagnose and replace these components on all makes, including electric water pumps common on BMW and other modern engines.
Common signs
Symptoms worth checking
- Coolant leaking from the front of the engine or radiator
- Temperature fluctuating or slow to warm up
- Overheating in traffic
- Whining or grinding from the pump
- Coolant pump fault messages
Three parts, different failures
Radiators can corrode, crack or block internally. Mechanical water pumps can leak from their seal or wear their bearing; electric pumps can fail electronically. Thermostats can stick open (slow warm-up) or closed (overheating).
Live data and temperature measurements help us distinguish between them.
What we check
- Pressure test
- Temperature data and thermostat operation
- Pump operation, leaks and noise
- Radiator flow and fins
- Electrical control of pumps/thermostats
What we can do
- Radiator replacement
- Mechanical and electric water pump replacement
- Thermostat and housing replacement
- Coolant replacement and bleeding
How it works
The process
- 01
Diagnose the failing component.
- 02
Quote the repair.
- 03
Replace and bleed the system.
- 04
Confirm correct operating temperature.
Why The Factory
Main-dealer capability, independent service
A Master Technician-led workshop with seven mechanical ramps, a dedicated MOT ramp and dealer-level diagnostics. Faults are shown to you and additional work is quoted before it goes ahead.
We stand behind the work we carry out. Parts and workmanship are covered in accordance with your statutory rights and any applicable manufacturer or supplier warranty. Please ask us for details relevant to your repair.
- Diagnostics for electric pump and thermostat control
- BMW electric water pump experience
Free local collection & return
Available by arrangement within approximately five miles of our Sunbury-on-Thames workshop. Further afield? Just ask us.
FAQs
Radiator, Water Pump & Thermostat: your questions answered
How do I know if my water pump is failing?
Coolant leaks near the pump, noise, overheating or — for electric pumps — warning messages are common signs.
What are the symptoms of a stuck thermostat?
Stuck open: slow warm-up and poor heater output. Stuck closed: rapid overheating.
Why is my radiator leaking coolant?
Corrosion, age-related cracking of plastic tanks, or impact damage.
Can a faulty water pump cause overheating?
Yes. If coolant isn’t circulated properly the engine can overheat quickly.
Can you diagnose electric water pump faults on modern vehicles?
Yes. We use diagnostic equipment to test pump operation and control.
Related services
Cooling System Repairs
Overheating, coolant loss and heater problems diagnosed and repaired.
Timing Belt / Cambelt Replacement
Cambelt replacement with the correct kit and checks for your engine.
Engine Repairs
Diagnosis and repair of misfires, leaks, poor running and mechanical faults.
BMW Specialist
Independent BMW servicing, diagnostics and repair.
Need help with radiator, water pump & thermostat?
Send your registration and a quick description on WhatsApp, or call the workshop.
The Factory, Harris Way, Sunbury-on-Thames TW16 7EL