i have a 6 speed MCS. i took a road trip today. 300 highway miles and i averaged 29 MPG. could this be effects of too much oil? my oil level is 1 inch above the top nodule on the dip stick. was filled at the dealer 2000 miles ago. i have noticed a sharp decline in my MPG since then. i also noticed my coolant is below the low point in the coolant tank. and after 150 miles of highway driving my tailpipes had liquid pooling and dripping out of them. it seemed like water. is my engine ruined? car drives like normal and still delivers great power.

 

Water is a normal byproduct of the exhaust system. Nothing to worry there. But 1 inch over the max mark is a total disrespect for the dipstick designer/engineer. I always make sure the oil level is somewhere in the upper part between the min. and max. I would learn to change oil at home if possible.

 

im worried about damage. its literally the distance between the min and max above the max. and the oil is quite dirty for just being changed a month ago. how could the MINI dealership do this? am i just being to paranoid? i have no smoke coming out of my tailpipes.

 

Call the dealer and tell him about it. I wouldn't drive the car until talking to him.

 

if damage would have happened wouldnt it have happened already. i drive the car hard at times. and like i said i drove 300 miles today and hit 6000 RPMs several times during the trip. my point is, how can the dealer tell damage was done and wouldnt it have happened already. there has to be some leeway in the engine for eccess oil. if my dealer was stupid enough to "overfill" this must happen every day. wouldnt i notice any damage within the first 2000 miles? i guess i just dont want the dealer to have to take oil out and then have engine failure at 120000 miles and this be the cause. im just trying to be chill about this whole thing and hope maybe its not a huge deal.

is engine failure due to eccess overfill quick and noticable or slow and drawn out?

 

You are trying to quantify the overfill and I dont think this is possible.

Two things. Revving the engine to 6000 rpm, when at operating temp, will not do damage. However overfill of oil could cause damage due to foaming of oil. Being that I have never been inside a mini engine but many bmw engines I would think this would be possible for the crank to whip the oil.

Now the quantifying part for engine damage is the tough part. Can one tell if damage was done? Well you could to a compression check on the motor to see if the cylinders have the same balance of pressure and that this figure is within parameters set forth in the service manual. Also a cold and hot operating oil pressure with fresh oil could give you an indication of how the bottom end is doing as in the bearing clearances.

Other than the above if you do not see issues I would change the oil out with new or at the very least get that extra oil out of the system.

Being that you had the probability of foaming the oil I would change it out and send a sample to blackstone laboratories for a proper diagnosis of the oil. This data could be brought to your service advisers attention but how you would capture the fact that the damage was done by there overfill I do not know.

 

thanks for the informative reply. i have also heard that synthetic or semi synthetic oils have anti foam agents added to them to prevent this potential problem. is this true?

 

Let car sit overnight. Check oil level again before starting engine for the first time of the day.
Jim

 

will do.

 

These additives have limitations as the intent is not to stop foaming of a crank running through the oil but more for stopping foaming due to pumping of the oil

 

But doesn't the engine use a dry sump lubrication system, so the crank isn't just sitting in a bath of oil where it could froth it up......by the way, would a check engine light come on if the oil is overfilled?

 

I would be amazed if bmw went with a dry sump on this motor and for all that I can find it is a wet sump in which case the crank is suspended over the oil. If you fill it up enough the counterweights will stir the oil.

 

I'd at least put the dealer on notice for future claims--even try to wrangle a 100,000 warranty.

I'm pretty pushy, though!

 

For something like this happening I would do the same. Escalate the situation to the manager of the dealership. You have a founded concern and they need to remedy the situation not you. Beat them up

 

In the meantime, you could drain out some of the xs oil.

YD

 

I hate to say it, but if your oil level is high and the coolant level is low and you notice water dripping from your tail pipe, you either have a blown head gasket or a cracked block. Don't run the engine any more! With coolant in the oil, the lubricating ability is compromised and you will only do further damage. I would get the car towed to a mechanic and have them look at it.

 

Water out of the tail pipes is from the catalyst converting the gases to steam and other gases instead of carbon monoxide and other gases. If the temperature is right you will see the water dripping off the pipes. A sure tell tail of a blown head gasket would be brown water/oil mix on the oil filler cap.

 

The water is actually a by-product of the combustion of a hydrocarbon, all the other reactions should be gas to gas reactions, but yes a little water is normal. Usually it stays as steam and never condenses unless the system is cold though.

The combination of low coolant, high oil, and pooling water after a long drive is awfully suspicious... Head gasket was my first thought when reading the original post. Certainly enough that getting it checked out before taking the car anywhere else is worthwhile.

Other bad head gasket signs: Overheating or more fan running than normal, sweet smelling exhaust, or bluish vapor in the exhaust (like you'd see in the morning) even when the car is warm.

 

I had my dealership overfill the oil by around quart the first time they changed the oil. I didn't check it for a while since I figured MINI wouldn't do something that stupid. I brought it in and they drained the excess oil. The next time they changed the oil they overfilled it as well. I caught that right away, car seems to be running fine. However I'm probably going to sell it once the warranty is up.

 

i checked it first thing in the morning and the oil was about 1/8-1/4 of an inch above the top fill line. so a 1/4 quart at the most. car was also on a slight forward slope. that shouldnt cause any problems. the oil was awfully dark for being changed 1500 miles prior. and with the car sitting overnight the coolant was about a half inch+ below the minimun line. i looked in the resevoir and there is no "oil slick" floating on the surface of the coolant. i have also not seen and water in my tailpipes since. no odor or smoke at all either. also under the oil filler cap looks clean and free of and brown foam. im going to continue to drive it and see what happens. and if something blows im under warranty till 100,000 (geico extended warrant rocks) and i get a new engine. im also going to let my dealer know about this and keep a closer eye next time.

BTW i had a cracked head gasket on my audi TT. it would suck my coolant dry on a daily basis and i saw the brown foam in the oil filler cap. it had 58,000 miles on it. 1.8T