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STC493 - Non-Return Valve Repair Kit

Original price - Original price €10,10
Original price
€10,10
€10,10 - €10,10
Current price €10,10
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.
Non-Return Valve for the brake servo vacuum circuit.

This one-way valve sits in the vacuum line between the engine inlet manifold (or vacuum pump) and the brake servo. It allows air to be drawn out of the servo to build vacuum, then seals to hold that vacuum so the servo retains braking assistance when manifold vacuum drops. Fitted to applications without ABS.
Vehicle Model Land Rover Defender up to 2016
Fitment Notes DEFENDER 1987-2006 — Master cylinder & servo, less ABS, from VIN HA701010
Alternative Codes
STC493

In stock 18 units
14 · Gouda 4 · 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 does the STC493 non-return valve do?
The STC493 non-return valve is a one-way valve in the brake servo vacuum line between the engine inlet manifold and the servo. It lets air be drawn out to build vacuum, then seals to hold it, so the servo keeps braking assistance when manifold vacuum drops.
Which vehicles does this non-return valve kit fit?
This valve kit fits the Defender (1987-2006) with the master cylinder and servo setup, on non-ABS vehicles from VIN HA701010. It's specific to the less-ABS braking system, so confirm your Defender doesn't have ABS before ordering.
What are the signs the brake servo non-return valve has failed?
A failed non-return valve usually gives a hard brake pedal and weak servo assistance, because the servo can't hold vacuum. You might also hear a hiss at the valve. Braking effort rises noticeably, so the valve is renewed once assistance is lost.
How do I confirm this fits my Defender?
Check that your Defender is a non-ABS vehicle built from VIN HA701010, since this valve serves the less-ABS master cylinder and servo. Using your VIN confirms the braking setup, as ABS Defenders use a different vacuum arrangement.