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STC4735 - Radiator Cap – 10 lbs

Original price - Original price €12,00
Original price
€12,00
€12,00 - €12,00
Current price €12,00
Aftermarket Part
Aftermarket: Quality alternative. This is a quality alternative, designed to fit and function like the original part, often at a more competitive price.
Radiator Cap Pressure-relief filler cap for the engine cooling system, sealing the radiator or coolant expansion tank filler neck.

Rated to release at 10 lb/in² (approximately 0.7 bar). It holds the cooling system under pressure to raise the coolant boiling point, and its sprung valve vents excess pressure to the overflow once the rated figure is exceeded.
Vehicle Model Land Rover Defender up to 2016
Land Rover Series 2 and 3
Fitment Notes DEFENDER 1987-2006 — 4-cyl naturally-aspirated expansion tank cap; excludes TDi & Td5 (from VIN LA932798)
SERIES 2 & 2A — 9lb type
SERIES 3 — 2.25 Petrol & 2.6 6-cyl Petrol
Alternative Codes
217417STC4735STC4735ES242399GRC115GRC116

In stock 9 units
8 · Gouda 1 · Drachten
Express delivery available

When will my order arrive?
  • Order before 15:00 (Mon–Fri): same-day dispatch for in-stock items.
  • UPS Express (order before 14:00): dispatched today, delivered tomorrow where available.
  • Netherlands / Belgium / Germany: 2–4 working days.
  • Other EU countries + UK: 4–8 working days.
  • Outside EU/UK: delivery times vary — contact us for an estimate.

Items may ship from multiple warehouses at no extra cost.

Job kits containing this part

This part is included in 0 job kit(s) below. Pick the kit that matches your vehicle and job, then add what you need.

Frequently asked questions

What is the radiator cap and what does it do?
The radiator cap (STC4735) is a pressure-relief filler cap for the Land Rover cooling system. It seals the expansion tank or radiator filler neck and holds the system under pressure to raise the coolant boiling point. Its sprung valve vents excess pressure to the overflow once the rated figure is reached.
What pressure is this radiator cap rated to?
This radiator cap is rated to 10 lb/in², roughly 0.7 bar. It keeps the cooling system pressurised to that figure, then releases to the overflow above it. Land Rover used different cap ratings across models, so matching the correct pressure to your engine matters.
Which Land Rovers does this 10 lb cap fit?
This 10 lb radiator cap fits the Land Rover Defender from 1987 to 2006 with the 4-cylinder naturally-aspirated petrol engine, and the Series 3 with 2.25 petrol or 2.6 6-cylinder petrol. It doesn't fit the TDi or Td5 diesel models.
Why does a radiator cap fail, and when should it be replaced?
A radiator cap fails when its rubber seal hardens or the pressure spring weakens, so it no longer holds the rated 10 lb. Typical signs are coolant loss, overheating, or a collapsed expansion tank. Caps are usually replaced as a service item once they stop sealing.