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ERR4686BLUE - Filler Plug – Blue Anodised Aluminium

Original price - Original price €8,70
Original price
€8,70
€8,70 - €8,70
Current price €8,70
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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.
Filler Plug in blue anodised aluminium, replacing the standard cooling system filler and blanking plug at the thermostat housing.

Seals against a supplied O-ring. The anodised alloy finish resists corrosion in the engine bay. Also serves as a cooling system drain and filler plug on V8 petrol applications.
Vehicle Model Land Rover Defender up to 2016
Land Rover Discovery 1 1989-1998 (L318)
Range Rover Classic up to 1994
Range Rover Classic 1994-2001 (P38)
Fitment Notes DEFENDER 1986-2006 — 300 TDi, thermostat housing plug
DISCOVERY 1 1989-1998 — 300 TDi, thermostat housing plug
RANGE ROVER CLASSIC 1992-1994 — 300 TDi, thermostat housing plug
RANGE ROVER P38 1994-2001 — 4.0L/4.6L V8 Petrol, radiator/cooling system drain-filler plug
Blue anodised alloy dress-up plug, includes O-ring
Alternative Codes
ERR4686BLUE

In stock 9 units
9 · Gouda 0 · 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 ERR4686BLUE filler plug used for?
The ERR4686BLUE filler plug replaces the standard cooling system filler and blanking plug at the thermostat housing. It's a blue anodised aluminium plug that seals against a supplied O-ring, resisting corrosion in the engine bay while tidying the cooling system's appearance.
Which Land Rovers does this filler plug fit?
This filler plug fits the 300 TDi Defender, Discovery 1 and Range Rover Classic at the thermostat housing, and the Range Rover P38 4.0L/4.6L V8 as a radiator cooling system drain-filler plug. Check which plug your engine uses before ordering.
Does the ERR4686BLUE come with a seal?
Yes, the ERR4686BLUE includes an O-ring, so it seals the cooling system without needing a separate gasket. Fit the O-ring lightly lubricated with coolant and tighten by hand plus a nip, since it's an aluminium plug into an alloy housing and can strip if overtightened.