BMW oil filter housing and rocker cover gasket leaks

Which BMWs are affected?

This page covers oil leaks from the oil filter housing gasket and the rocker cover gasket. For other BMW and MINI work, see our BMW and MINI specialist page.

Oil filter housing gasket. The leak is known on BMW’s six-cylinder N-series petrol engines and on the N20 2.0 four-cylinder petrol.

Rocker cover gasket. The rocker cover sits on top of the engine. We check its gasket whenever we trace an oil leak.

If you are not sure which engine your BMW has, put the registration in the enquiry form and we will check.

What are the symptoms?

The sign to look for is oil around the front of the engine.

Oil runs downwards, so where you notice it is not always where it starts. When you book, tell us:

• where you have seen oil
• whether you have been topping up the oil, and roughly how often
• whether any warning lights are on

What causes it?

The oil filter housing is sealed to the engine with gaskets. With age the gasket dries out and shrinks, and oil starts to seep past it.

The leak matters because of where the oil goes. Oil from the housing can reach the drive belt, which makes the belt swell and break down. The oil can also contaminate the coolant. That is why it is worth fixing the leak early, before the belt or the coolant suffer.

How do you confirm where the leak is before fitting parts?

A fault code is not a repair, and a wet engine is not a diagnosis. Before we quote for any parts, we:

• inspect the engine from above and below
• trace the oil back to the highest point that is wet, because oil runs down and can make a lower part look like the source
• check the drive belt for oil damage
• check the coolant for signs of oil

We then show you what we found, with photos, and send a written price. No part is fitted until you give your written approval.

What does the repair involve?

For an oil filter housing leak, we replace both of the housing’s gaskets, then top up the oil and the coolant. On the N20, the inlet manifold has to be moved to reach the housing.

If the inspection shows the rocker cover gasket is leaking too, or the drive belt has been damaged by oil, we show you the evidence and price each item separately. Nothing extra is done without your written approval.

Once the work is done, we run the engine, check that the leak has stopped and verify the repair, including a road test where appropriate.

How long does an oil leak repair take?

It depends on which gasket is leaking, on the engine, and on whether the drive belt also needs attention. On the N20 there is more to remove, because the inlet manifold has to be moved.

Before any work starts, you get a written price and a promised time for your next update. If the car needs to stay with us, ask about a courtesy car when you book.

Is there a recall for BMW oil leaks?

Whether a recall applies depends on the individual car, so check your registration on gov.uk. Recall work is done by BMW’s network, not by us.