Reasons Behind Crank Seal Oil Leaks in Minis

Crank Seal Oil Leaks

Oil leaks are a common problem in any vehicle, and they often are indicators of larger problems in your car. Older Minis have a tendency to develop oil leaks when their crankshaft seals begin to wear down, crack, and break. Broken crankshaft seals can lead to major engine trouble if they are left unattended.

What is the Crankshaft Seal?

The crankshaft seal is attached to the front of the engine. It seals the end of the crankshaft together with the timing cover. These seals are usually made of metal and rubber or silicone, and are installed in the front timing cover to seal the end of the crankshaft as it turns. Crankshaft seals are a simple component, but they serve a very important purpose. They keep the oil, which is tossed by the rotating crankshaft, from leaking outside of the crankcase. If they fail, they cause leaks which can make a mess and can put the engine at risk of serious damage if they are not dealt with quickly.

The crankcase sits below the cylinders and helps transfer the engine energy into the circular motion for your wheels, which makes your car move forward. For your crankshaft to function properly, it must be submerged in oil and friction-free. The crankshaft seals have the job of keeping this oil in the crankshaft cavity and not leaking out everywhere else.

Crankshaft Seal Life-span

Crankshafts seals do not last forever. If you are nearing 100,000 miles, then your crankshaft seal is near the end of its recommended service life. Manufacturers have a service interval that they recommend for most vehicle parts. By servicing your crankshaft seal near the recommended service interval, you can prevent the seal from failing, and save yourself from a lot of other problems that come as a result of a failed crankshaft seal.

Why Do Crankshaft Seals Fail?

Over time the crankshaft seal dries out and becomes brittle, just like any rubber component. This may be due to the heat from the engine or from the friction it experiences between the crankshaft and the timing cover. Also, oil itself eventually degrades rubber vehicle parts. When the rubber loses its elasticity, it will eventually form cracks and then break.

When these breaks occur, you will start to have oil leaks. The small leaks at first tend to accumulate oil underneath the engine. As the leaks get larger, you may notice an oil drip at the front side of the engine as well. Additionally, oil may spray on the clutch which will cause it to slip occasionally. These are all warning signs that you need to replace your crankshaft seals.

How Do You Fix a Cracked or Broken Crankshaft Seal?

Once a crankshaft seal has cracked, it cannot be repaired, it must be replaced. On the plus side, the seals for minis are relatively inexpensive components. Unfortunately, they are not easy to replace.

1. The vehicle is raised up on jack stands
2. The crankshaft damper is removed
3. The timing belt is removed
4. The crankshaft seal is taken off and replaced
5. The timing belt and cover along is replaced, and the crankshaft damper is reinstalled
6. The engine accessory belts are reinstalled, and the vehicle is lowered off of the jack back to the ground

Fast Lane European Can Help

All vehicles have crankshafts and crankshaft seals, but Mini Coopers can be especially difficult to get into to replace. The German automotive specialists here at Fast Lane European are San Jose's leading BMW, Mini & Volvo service center since 2001. We give expert service to owners of Mini Coopers from all over San Jose, CAFast Lane European has expert European Auto Technicians on hand that can quickly and safely diagnose your oil leak and replace your crankshaft seals if necessary, making sure to inspect all the seals on your engine to prevent you from experiencing a similar problem on a different seal, just a few days, weeks, or months down the road.

Our factory certified service and diagnostic equipment along with our low labor rates make us the best choice for the service you need in San Jose. If you'd like us to inspect your oil leak or replace your crankshaft seal, or if you would just like to find out about our qualifications, please call us today. We look forward to giving you and your Mini our quality service.