Engine Oil Overfilled by Dealer

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Top Jimmy

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Mazda CX-7 GT AWD
I decided to take advantage of my dealer's free oil change offer at about 2200 miles on my vehicle. I now have 4200 miles on it.

I went ahead and checked the oil level last night (for the first time, I might add) because I thought the engine might be using some extra oil since it is still relatively new. Well, theoretically, at least, you are supposed to get a lower reading when the engine is cold so I was fully expecting to get a low-normal reading. Much to my surpise, the oil level was well above the "max" line; I mean like 1 inch or so above the line.

Again, I checked the oil level this morning after driving to work and after letting it sit for 10 minutes and the level was about the same as last night; not really any higher as I might have expected but still way above the max line.

I proceeded to take it to the dealership knowing full well that they would probably try to cover their asses and say the level was barely above normal. Well, to no surprise of my own, they told me just that; that the oil was merely 1/4 quart above normal and that they went ahead and drained that 1/4 quart and that everything was fine. I guess I have to take their word that they drained only 1/4 quart but I certainly did not witness it for myself.

What kind of damage did/could the overfill of oil have caused to my engine after driving about 2000 miles with the oil overfilled? I do have it documented that it was overfilled by 1/4 quart but I have a suspicion it had way more than that since the dipstick was reading about 1 inch or more above the max line. Any input would be helpful.
 
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I changed my own oil and filter and put in the stated 6 quarts and it was about an inch above the max line. I asked the dealer and they said you shouldn't overfill it, yet its the amount the manual says to put in. Obviously the dipstick is either not calibrated right, or it should only have 5.5 quarts, or maybe 5. This could end up with a TSB for the dipstick or a typo fixed in the manual! It sisn't seem to hurt anything as I drove it 4k on that oil change.
 
oil overfill

OK, same thing happened to me on Saturday...had the dealer change my oil then 52 miles later I'm seeing blueish/white smoke coming from my exhaust pipes...stopped the car, checked the oil and it was about a half inch above the max line. There was heavy black soot in the exhaust pipes. Took it back to the dealer and of course they said "not a problem"...I said why is it you say it's not a problem but the manual say's "CAUTION, do not overfill the oil as engine damage may occur"??? He couldn't explain that...then proceeded to tell me this was normal. I said look, I didn't fall off the turnip truck yesterday, so I an't buying that story. They checked everything out and drained the oil to the correct level. Took pictures of exhaust and heavily sooted spark plugs (11,300 miles!!!), checked the turbo and said everything is fine. I made sure to get good documentation and even contacted Mazda USA hot line and got a case # assigned to document this event. I know this engine can go easily 150,000 miles with proper care so I wanted some evidence that something occurred at 11,000 miles in case everyone get's amnesia if I do have a problem after the warranty is up...lesson learned...always check the oil level before you leave....
 
I just checked my oil because I had the hood open... at 450 miles, oil filled from the factory, it sits about 1/4 - 1/2" above the max fill line.
 
So can someone tell me the catastrophic effects of a *slightly* overfilled oil pan? I mean if it's way over filled I can come up with several senarios that could cause catastrophic problems, but not slightly. Is there something I'm missing because of the turbo? Please explain.

I normally run extra oil in one of my cars because I take it to the track and have yet to get a pan with a windage tray. No adverse effects for the 11 years I've been doing this and I will guarantee that I put more stress and run higher rpm than on a street driven CX-7. *Knock on wood*

Oh, btw, isn't the heavy soot normally seen when the engine runs rich, like ours reportedly run way too rich?
 
Overfilling does not cause higher pressure. Your oil pump works at the same pressure regardless of the oil level, unless it's so low that it begins to suck air, at which time pressure will go down.

What you do have to worry about is oil intrusion into one or more cylinders if severly overfilled. The interior of the engine is designed for a specific capacity of oil, and when a great deal more is introduced, it will start looking for places to go. The first opportunity for escape will be past the oil rings and into the combustion chambers, where plug fouling and other nasties start to take place. A severly overfilled engine can cause oil to enter the exaust tract, and it's hell on a catalytic converter.

As far as I can tell, my MS6 has been overfilled every time the oil's been changed. It was overfilled when I took possession and I changed the oil myself a short while later, pouring in the required 6 quarts and it again reads about 1/2 inch above full. I've had no issues thus far. If you're getting some odd behavior, it may be something more serious than just a slight overfill, so definitely take it in.
 
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It will not increase the Oil Pressure.

It Will raise the Crankcase Pressure
It Will cause stress on the seals
In Extreme Cases it will froth the oil as the crank hits it which will greatly reduce its effectiveness.
 
I have a reference number in at Mazda to decipher this issue. They have not got back to me yet. Also my local dealer is going to do the next oil change to verify if 6 qts really does overfill it on the dipstick.
 
My dealer said to wait for next oil change and they will do it under warranty to determine if the 6 quarts is off.
 
rcllkl said:
OK, same thing happened to me on Saturday...had the dealer change my oil then 52 miles later I'm seeing blueish/white smoke coming from my exhaust pipes...stopped the car, checked the oil and it was about a half inch above the max line. There was heavy black soot in the exhaust pipes. Took it back to the dealer and of course they said "not a problem"...I said why is it you say it's not a problem but the manual say's "CAUTION, do not overfill the oil as engine damage may occur"??? He couldn't explain that...then proceeded to tell me this was normal. I said look, I didn't fall off the turnip truck yesterday, so I an't buying that story. They checked everything out and drained the oil to the correct level. Took pictures of exhaust and heavily sooted spark plugs (11,300 miles!!!), checked the turbo and said everything is fine. I made sure to get good documentation and even contacted Mazda USA hot line and got a case # assigned to document this event. I know this engine can go easily 150,000 miles with proper care so I wanted some evidence that something occurred at 11,000 miles in case everyone get's amnesia if I do have a problem after the warranty is up...lesson learned...always check the oil level before you leave....
Click to expand...

back when my ride was having problems, Mazda instructed me on a procedure to manually clean the spark plugs. In Park, keep the tach around 4k rpm, its supposed to burn off excess carbon buiild up - when the tach drops (done by the computer), the process is done.

my sparks were heavily soooooted at 5 & 6k miles.
 
Man I can't believe dealer and manufacturers are so dumb and are barely seing this. How dificult is it to physically check a car after you've done a service. I used to have a problem with the pumps at the dealer I worked for where they would either not pump or double pump the oil. Some of the guys that worked next to me wouldn't check their car. Imagine driving around with an extra 5 qts of oil, yeah that's got to suck.
 
My brother took his VW turbo to a quick-change oil shop and they overfilled his engine. Well, while cruising down the interstate he noticed a large cloud of smoke pouring out of the back of his car. Needless to say, he had to pull over because engine performance dropped off dramatically. The turbo was soaked in oil because the seals were blown out. The oil wasn't draining back into pan because the oil level in pan was above the drain line from turbo causing the oil pressure in turbo to build up. He took them to court and won his case and shop had to replace turbo.
 
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Brian MP5T said:
It will not increase the Oil Pressure.

It Will raise the Crankcase Pressure
It Will cause stress on the seals
In Extreme Cases it will froth the oil as the crank hits it which will greatly reduce its effectiveness.
Click to expand...

Thank you.(yippy)
 
So is anyone else seeing this blueish/white smoke coming from their exhaust? Mine seems to occur while in stop and go traffic. If sitting at a light for some time, then accelerate away I see the smoke. Dealer says it's condensation building up and then hitting the catalitic converter turns to steam!! Funny thing is this never happened before they overfilled the oil.
 
It will take some time for it to all burn out, there are a lot of spots the oil can sit so it will be some time. You can try to help it but I don't really know how much it may help or hurt. I had my turbo leaking oil, when I finally fixed it I back my car half in the drive way and put the hose in the exhaust. It smoked a bunch and it did smell like it helped but I do have a straight through exhaust so that may not work for everybody.
 
changed my oil last night. Same issue. Put in about 5.2 quarts - taht put the oil level right on the full line. Checked it again tonight after coming home (the car was hot), the oil was about 1/2" above the full line. So I drained some oil out bringing the level back to the full mark (little hole). This means that I put about 5 quarts (or under) to bring the oil level to full. where the heck are the 6 quarts coming from? can the manual be off by a freaking quart?!?!?
 
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