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LR176861LR - Cap - Overflow Container by LAND ROVERCooling or Heating Part Land Rover Range Rover

LR176861LR - Coolant Expansion Tank Cap

- €18,90
€18,90
€18,90 - €18,90
€18,90
Genuine Part
Genuine: Original manufacturer part. This product is the original part designed and produced by the vehicle manufacturer.
Coolant Expansion Tank Cap - pressurised filler cap for the coolant expansion and overflow container in the engine cooling system.

The cap sets the operating pressure of the whole cooling circuit. A calibrated relief valve inside it keeps the coolant under pressure so its boiling point rises well above atmospheric, protecting against local boiling at the cylinder head and cavitation at the pump; once the rated pressure is exceeded the valve lifts and vents into the overflow path. As the engine cools and the coolant contracts, a vacuum valve in the same cap admits air and coolant back into the system so hoses and the tank are not drawn in.

Symptoms of a failing cap are a system that will not hold pressure on test, coolant disappearing without a visible leak, and overheating that only appears on long climbs or when towing. The cap is a consumable and is normally renewed alongside the expansion tank.
Vehicle Model Land Rover Defender New 2020+
Land Rover Discovery 4 2010-2016 (L319)
Land Rover Discovery 5 2017+ (L462)
Range Rover 2002-2012 (L322)
Range Rover 2013-2022 (L405)
Range Rover Sport 2005-2013 (L320)
Range Rover Sport 2014-2022 (L494)
Fitment Notes DISCOVERY 4 2010-2016 — 3.0L V6 Diesel, 4.0/5.0 V8 Petrol
DISCOVERY 5 2017 on — engine cooling
NEW DEFENDER 2020 on (L663) — 2.0L/3.0L/5.0L/4.4L
RANGE ROVER L322 2010-2012 — 5.0 V8 NA/SC
RANGE ROVER L405 2013 on — 3.0L Diesel, 5.0 V8 NA/SC
RANGE ROVER SPORT L320 2010-2013 — 5.0 V8 NA/SC
RANGE ROVER SPORT L494 2014 on — 3.0L, 5.0 V8
Alternative Codes
LR176861LR

Available to order 2–3 weeks

Not currently in stock. Order now — typically ships within 2–3 weeks.

Need it faster? Contact us about express import (2–5 business days).

When will my order arrive?

This item is ordered from our supplier on request. Typical lead time is 2–3 weeks from order confirmation.

  • Netherlands / Belgium / Germany: 2–4 working days after dispatch.
  • Other EU countries + UK: 4–8 working days after dispatch.
  • Outside EU/UK: contact us for an estimate.

Need it faster? Express import available in 2–5 business days — contact us before ordering.

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 does the coolant expansion tank cap do on a Land Rover?
The coolant expansion tank cap seals and pressurises the cooling system. A calibrated relief valve inside holds the coolant under pressure, which raises its boiling point and lets the system run hotter without boiling. It also relieves excess pressure and lets the circuit draw coolant back as it cools.
Where is the expansion tank cap fitted?
The expansion tank cap fits on top of the coolant expansion and overflow tank in the engine cooling system. It's the point you check coolant level and top up from, and it sets the operating pressure for the whole cooling circuit.
What are the signs the coolant cap needs replacing?
A worn coolant cap typically shows as coolant loss, overheating, or a system that won't hold pressure. The rubber seal and relief valve inside harden over time, so a cap that no longer seals can cause boil-over even when the rest of the cooling system is healthy.
Which Land Rover models does this cap fit?
This cap fits the New Defender 2020 on, Discovery 4 and Discovery 5, Range Rover L322 and L405, and Range Rover Sport L320 and L494. Check your engine variant against the listing to confirm the correct cooling system application.