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ERR1086 - Oil Pressure Relief Valve Plug

Original price - Original price €18,70
Original price
€18,70
€18,70 - €18,70
Current price €18,70
Genuine Part
Genuine: Original manufacturer part. This product is the original part designed and produced by the vehicle manufacturer.
Oil Pressure Relief Valve Plug seals the oil pressure relief valve bore in the cylinder block of the 300Tdi engine.

The plug retains the relief valve spring and piston assembly within their machined bore in the engine block. It must maintain a secure, leak-free seal under sustained oil pressure. Replacement is required if the plug is damaged during disassembly or if oil seepage is observed at that location.
Vehicle Model Land Rover Defender up to 2016
Land Rover Discovery 1 1989-1998 (L318)
Range Rover Classic up to 1994
Fitment Notes DEFENDER 1987-2006 — 2.5L 300 TDi Diesel
DISCOVERY 1 1989-1998 — 2.5L 300 TDi, to VIN (V)MA081992
RANGE ROVER CLASSIC 1992-1994 — 2.5L TDi
Alternative Codes
ERR1086

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 dayscontact 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 is the oil pressure relief valve plug (ERR1086) for?
The oil pressure relief valve plug seals the relief valve bore in the cylinder block of the 2.5L 300Tdi engine. It holds the relief valve spring and piston in their machined bore and keeps an oil-tight seal under full oil pressure.
When does this plug need replacing?
Replace the plug if it's damaged during disassembly or if you see oil weeping from the relief valve location on the 300Tdi block. As a Genuine Land Rover part, it restores the correct sealing face that a distorted or old plug can lose.
Which models take the ERR1086 plug?
The ERR1086 plug fits the 2.5L 300Tdi Defender (1987-2006), Discovery 1 (1989-1998) up to VIN MA081992, and Range Rover Classic (1992-1994). On the Discovery 1, check your VIN against that break before ordering.