I think Don Moffet hit it dead on!  We spent the summer chasing leaks in my supercharged 1380 and in every case we found a faulty install or the reason, even a warped timing chain cover, and need for another engine breather.  I have now had 3 autocrosses and still no leaks but of course more time will tell     

we call it "The Signature"

My Moke leaked like a sieve and then I went on a anti leak jihad. Removed, sanded, agsket, etc and no more leaks.

It still wept at some places but there was none of the previous Exxon Valdez shananeegans.

mini's don't leak oil, they mark there territory. 

Mine had a VERY slow and unpredictable leak which turned out to be a pinhole in the oil line that connects to the oil pressure gauge.  The pinhole was on the underside of the line and the oil flowed downwards until it dripped from the oil filter assembly.  I assumed it was a bad coupling where the metal oil line connects to the part that the filter screws into.  I figured out otherwise when the pinhole opened up to a slash in the brittle rubber, dumping a quart worth of oil onto the street in front of my house?  Moral of the story?  REALLY try to pin down those leaks.  They may be easy to fix or hard, but at least you'll know the WHY.  Mine was easily fixable once I traced the leak to the source.  I COULD have blown the engine had the leak not begun while the car was warming up.

my mini leaked, until I replaced the driveshaft seals (and bushings at the same time - important for driveshaft seal life) and rod shift seal, and now it doesn't leak, and hasn't for several years since.

Norm

My Mini did not leak, I was amazed.  The key is careful assembly with just a touch of sealer in the proper places.

When it stops leaking, then you know you have a problem!

When mine stops leaking, I know it's out.

Dan -

I'll pass that along to the current owner. As it turns out, my VTEC does leak a bit, so I feel better.

BTW, I find that a small priority shipping box (your shipper of choice) with the face cut out and filled with some kitty litter (again, your choice) works quite well.

N J

Give it time.... it is just lulling you into complacency! Then.... WHAM!

Mine dripped oil unil I put a new rod change linkage seal in it. Sorted.

N J

mine doesn't, but than it has a vtec in it

You'll probably get more reasons for leaks than ther are Mini owners. But it all has to do with how well and carefully various gaskets and seals are installed and maintained. For example, tighter isn't always better. Take for instance rocker cover gasgets. Putting them on is generally easy but you have to be meticulous. The metal sealing surfaces have to be absolutely clean and free of any trace of oil. Then you need to get a good, reliable bonding agent such as Permatex spray adhesive and get the gasket to sit fully even and straight. A tacky rather than slippery adhesive sometimes helps in getting the gasket to stay put. Then you lower the rocker cover carefuly into place and tighten the bolts down evenly and gently. You only need enough pressure to hold the gasket in place, not compress it. Too much pressure only distorts the gasket. Similarly, it takes real care to install crankshaft and driveshaft oil seals so that they aren't distorted or scratched when passing over splines etc.  But because they are wearing surfaces (the shaft turns, rubbing on the seal) and the sealing material ages, they eventually will leak. My car's driveshaft seals leak a wee bit when it is left sitting unused, but not if it is driven regularly. I think someone once wrote here that they tend to dry out when not shifted regularly. On other cars, air conditioning pumps leak when not uses regularly. I suspect new cars with AC are designed to turn on the AC when you set the controls to windscreen defrost to activate the pump. It seems really counter-productive to have AC come on when it is -40 and you're trying to get frost off the inside of the windshield.

Speaking abount anti-freeze, in normal conditions, a Mini should not leak any. But you still need to check the level because most Minis do not have an expansion tank and need an air space in the top of the rad, unlike modern cars. Minis also do not generally have an overflow tank like new cars either. So if the rad gets too full, or the engine gets too hot, the coolant will expand, over-pressuring the rad cap and pushing a bit of liquid or vapour out the overflow tube, landing on the ground. So there is usually a constant slight evaporation loss due to this release of vapour. The Mini engine may overheat after you've turned it off because the head is hot and the coolant stops flowing. You can get localized boiling in the head which can push coolant out after you've parked and walked away. That's why new cars have catch tanks, which let the coolant siphon back in as the engine cools down.

Other antifreeze losses can occur in a Mini due to loose hose connections or old, tired hoses, corroded rads and heater cores, leaky heater valve, and the worst... a failed head gasket. The last isn't noticeable unless you experience rough running (leaking into a cylinder) or whitish creamy deposits around the oil filler cap and neck (leaking into the crankcase and mixing with the oil).

The basics of the technology in a Mini is over 50 years old. 50 years ago, these issues were commonplace in all cars, except maybe VW Beetles wich don't use coolant. Some of them had gasolene-fired heaters... rather not have that leak!

 

It's my understanding that nearly all mini's leave their mark.  Do most just drip oil or some anti-freeze as well?