vanster

About a month ago in mad dash to get ready for a yet another drive from the Bay Area to LA and back I did a full check ready.
It appeared to be low on oil so I added a quart, then another.
The car was on a slight slope and yes I over filled it. Some of the excess oil burped through the dip stick tube creating a mess. Upon my return I drained out the excess oil.

Have I done any damage?

SteveG

And then you drove 1,000 miles? Probably either burned off or collected in the plenum, and the excess in there went through the intake. Hard to say w/o seeing . . . . something. What do your plugs look like?
What's in the intake plenum -- as opposed to normal?

vanster

Yep, I drove about 800 miles. I went to two shops to ask them if I could put it on the lift and take out the oil and they both declined. Why do 928's scare mechanics? I should have just gone for an oil change. I had to get back in order to go to China the following day for a few weeks and I haven't driven it since. This weekend I will pull the plugs and the plenum and clean everything.

This falls into "what was I thinking"?

SeanR

I've had one of these around here for years that I just recently remembered I had. Perfect for what you are talking about. Sucks out only as much as you want it to.

dr bob

Take out the excess oil and drive it. It's quite possible you put in an 'extra' part of a quart. Regardless, whatever was done is done, and so far no catastrophic failures. Biggest risk is puking oil out, which you discovered, leaking from front and rear crank seals that stops when the oil level drops again, or leaking from cam and cover seals/gaskets if they don't drain back to the sump well. You probably burned a little extra oil due to more mist in the crankcase, but that's done when you go back to correct levels.

Move on, no problems, nothing to see here....

Barry Chan

Don't mean to hijack....while we are on the subject....
Do you check oil level when cold or hot?
When i check mine cold, it's down maybe 1/2 L but after fully warmed up and check....it's at the right level so correct oil level should be measured when cold or hot?
Barry

vanster

good question
If I remember correctly my 911's in my past life wanted their oil checked when running and hot. ( you can read this however you want). I checked the 928 cold also my driveway is not level, the back of the car was down. I put a quart in and it did not show any improvement as it was way below the add level which was odd. so I added quart, not much improvement, so I added another and then a half a quart them it was up to the mark. After about 250 miles when I stopped I could smell oil
and when getting gas, I noticed it not all over the engine bay but dripping like crazy in the front of the engine. The oil level on the stick was about .75 inch above the mark. It was then I realized what I had done.

dr bob

911's have a dry-sump tank, so you check level in the tank with engine running. I didn't realize that you'd put that much oil in it. You must have a pretty steep driveway! I've started mine on the steepest part of the hill here, and get the 'low oil level' warning on restart even when the level is fine on level ground. For yours, I'm guessing you'll want to do a little cleaning to get the oil off, then watch for continuing leaks to see if more work is needed.

And, FWIW, if I suddenly found that the car was a few quarts low, it would ring a bell to find out why, especially before romping up and down I-5 a couple times. Stuff that's different from normal gets my attention pretty quickly.

IcemanG17

Van
So your dipstick burped and spit the excess pressure out that made a mess...it is designed that way...the only other pressure relief in the system is to inject it into the airbox and intake...pull your air filter and look for oil spitting from the air pump fitting...that is what happens...if so clean it up and get a new filter....Given the low rpm load of your trip I think you will be fine...

I think you will be fine....given your trip was at fairly low load... BTW for what its worth...I poured 9 quarts of oil into my racer today with a 3/8th pan spacer....at room temp (say 70f) and it barely hit the bottom of the dipstick....and no it didn't run...but thats another story

bills928

I always thought that overfilling would damage your oil pump.... Is that not the case for 928's?

Alan

How does it get to the airpump? Can't see how this could happen on an S4+ - are earlier cars much different?

Alan

granprixweiss928

Ive heard that overfilling the oil can cause alot of excess splashing around in the pan and cause the oil to foam more. More gets sucked up into the intake, more gets burned off. Too much burning off can damage your catalytic converter.