Over the past couple of years a very serious issue has reared its head in many a 2001-2006 MINIs (aka the R50/R53/R52). The problem stems from oil seals or gaskets going bad (usually towards the front of the motor) and allowing oil to leak from the reservoir. If unchecked this could result in oil starvation and engine detonation.

I own an R50/R52/R53, What Should I Do?

For starters go check your oil… now. If it’s not low, make a mental note of the date (or better yet write it down) and be sure to check it again once a week (to see how to do this, you can watch DB’s demonstration below). If your oil is low head down to your MINI dealer and pick-up some of that unique BMW/MINI Castrol synthetic oil. And remember, once your car is older, it’s generally not wise to change oil from one brand to another. Now once your levels are where they need to be, look under the front of your car towards the front of the engine. If you see obvious signs of oil on the bottom of the engine (or even on the ground) you’ve got a problem. Schedule an appointment at your MINI dealer or local independent MINI shop.

The real problem

For this we turn to an expert: Chad Miller, owner of the MINI only shop Detroit Tuned.

>I see several leaks out of the early cars. The first one that leaks on all cars is the crank sensor. It has an o-ring on it and shrinks after it get hot after 30K and it allows oil pass it only when the car is running. It leaks down the front of the block and collects lots of dirt that comes through the radiator.  It will continue down the front of the motor to the pan and blow off when driving. It never drips as it is well above the oil level when the car is parked at any angle. The fix for it is to clean it up, pull it out, RTV it, Put it back in. To do this you HAVE to pull the front of the car off. 

>The second (and biggest) place I am seeing oil leak issues is the crank seal/gasket. This seal dries up and will also work its way out and allow oil to be pumped out as its right at the oil pump behind the crank damper. It’s the same on cooper or cooper S and it’s an easy fix once you pull the crank pulley. When this seal goes it will cover the front cover and the oil pan gasket and will make it look like the pan gasket is going. Sometimes it’s good to replace this seal first as it is easy and cheap before you pull the pan and replace that one. The seal is $13.48 the next one is the oil pan gasket. It’s a big job and very messy. (ED: This seems to be what most problems are that we’re hearing about.)

>You also have to pull the front end of to pull the air compressor. The gasket is a MINI only part, and lists for $36.71. There are no aftermarket parts for it. I always seal up the crank sensor when doing this job as you already have the front end off, even if the leak is not bad or not at all. I can almost guarantee that, at some point, it will start leaking. 

>I also see the oil cooler seals on the cooper S go. They get really hot and dry up and get hard. It starts as a drip, and can drip on the driveway. They can also just go and pump all the oil out of the motor. Again a very cheap part at $3.80 each (you need 2) and it’s a special square o-ring that you’re not going to just pick up anywhere. It’ll take about an hour to install and requires removing the oil filter to stop the drain of oil in to your work area. You can get to it through the drivers wheel well so it’s an easy install.

So there you have it. The majority of issues relate to the crank seal but there are a couple other that could also produce oil leaks. As Chad mentions, the parts aren’t pricey. However it’s the labor that gets the old parts off and the new parts on that is. In total it should run you around $800 at most MINI dealers. Independent shops should be a little cheaper.

As always if you’ve had any experience with the problem and the fix let us know. This is a growing problem in the R50/R52/R53 MINI world and will only get worse in the years ahead. We can only assume multiple aftermarkets solutions will be available soon and that MINI may even redesign the OEM part since the failure seems to be so widespread.