Valve stem seals are one of the most inconspicuous but enormously important components in the engine. They are located at the upper end of the valve guides and have the task of precisely regulating the oil flow. The aim: optimum lubrication without oil loss into the combustion chamber.

What do valve stem seals actually do?

While the valves are constantly moving up and down during operation, friction occurs between the valve stem and the guide. Oil is added to minimise this friction. The valve stem seal ensures that only the required amount of oil is supplied for lubrication – no more and no less. It prevents engine oil from entering the combustion chamber in an uncontrolled manner, where it would otherwise also be burnt.

Why do valve stem seals break?

Over time, the seals age due to heat, oil vapour and deposits. They become hard, porous or shrink. If this is the case, they can no longer fulfil their function – the oil seeps past the valves into the combustion chamber.

Typical signs of defective valve stem seals

Increased oil consumption, blue or black smoke from the exhaust – especially during cold starts or after long periods of inactivity – as well as traces of oil on the spark plugs or uneven engine running may indicate leaking valve stem seals. The defect is often only noticed during the emissions test or when there is a general loss of power.

Why it makes sense to switch in good time

If you wait too long, you not only risk higher oil consumption, but also damage to the catalytic converter and ignition system – not to mention the environmental impact. Replacing the seals in good time protects the engine and ensures that it runs cleanly and efficiently again.

We replace valve stem seals professionally, including all the necessary work steps – from disassembly and cleaning to professional installation of the new seals. On request, we can also check other relevant components at this time to prevent consequential damage.

		Combined offer
1st generation (R50-R53)	600,-	+ 600,- Timing chain*
2nd generation (R55-R61)	600,-	+ 600,- Timing chain*
Other MINIs	– upon request –

* When replacing the valve stem seals, it makes sense to replace the timing chain at the same time. We therefore offer a combined package for petrol engines.