So last Sunday (November 10th) I did an oil change. It'd been ~5,000 miles since my last one so it was definitely time. I put the
Cayman
up on my
QuickJack
, drained (what I thought was) almost all of the oil, dropped the filter housing and replaced the filter and o-ring, installed a magnetic drain
plug
, and put in 8 qts. of M1 0W-40 European Formula. I was very careful to measure 8 qts., as I didn't want to overfill it. Oil
cap
went back on; car went back on the ground; and I took her for a spin to get the engine warmed up. When I got back from my drive I pulled into my garage, which is level, and did the oil level check procedure. A minute later the oil showed as being at the top of the fill zone (
not
the top of the whole thing), so I was good to go.
Being the anal retentive Porsche owner that I am, I checked the oil level again on Wednesday (November 13th) after driving to work, and this time the oil showed as being at the top of the whole thing (i.e. one bar
higher
than the top of the fill zone). I waited a few minutes and tried it again, and it dropped back down to the top of the fill zone. I checked several more times over the next few days, and the level would go back and forth between the top of the fill zone and the top of the whole thing.
Thinking it's better to be safe than sorry, today I went to drain a little oil by pulling off the filter housing and letting all of the oil from the housing and filter drain out. Before doing so, I went and popped off the oil cap, and I found some yellow residue both on the bottom edge of the inside of my cap and on the inside of the oil filler hole (see pictures). I assume this is dried foam that made its way up the oil filler tube.
Clearly, then, I overfilled my oil. But I assume it wasn't "
too
" overfilled, because when I checked the level it would fluctuate between "as full as it should be" and "too full you idiot". So the obvious question is - how badly, if at all, have I hurt my engine by driving it Sunday - Friday this past week?
Since you have (according to your SIG) a 2011
Cayman
, and I'm assuming a base model.. you probably haven't done any damage to the engine. 2009 on engines have a built-in dry-sump, meaning it's separated from the moving bits of the engine by a baffle.. the danger in really overfilling the oil would be if the oil got up to the level of the crankshaft which would have a merry old time beating it to a froth. That would require a massive overfill of oil. The oil in your engine is kept separate from the moving bits for a reason - to prevent frothing.
The yellow junk around the oil
cap
is somewhat normal if the outside conditions are humid and cold and you're taking a lot of short trips. What causes it is moisture is being absorbed in the oil. It eventually evaporates out of the oil - and ends up depositing a film like that at any cold spots the vapor can reach. The oil
cap
being some distance from the engine is where it's usually seen, even on engines with a
cap
in a valve cover.
This is very common on engines used for a lot of short runs where the oil never reaches full operating temperature. Running the engine up to temperature every so often (something like a 20 mile high-speed drive) will help drive the moisture out of the oil.
Also the change in level - the oil fill gauge seems to be a step-readout. You see a complete segment as long as the level is somewhere in that segment. In this case I suspect you are right at the top of the top segment, and when the oil heated up it expanded a bit and triggered the segment above "full" - I wouldn't worry about it.
You likely did not hurt the motor, it may have sucked some oil into the
AOS
though. The oil level wiil generally read higher when it is hot, lower when cool. The stuff on your oil
cap
is from moisture. It comes from short drives that do not get the oil hot enough to burn off the water that is part of the air in the system. Longer drives, more fun, better for the car.
Edit, Don types faster than I do.
It is very easy to overfill your oil even when you put in the correct amount. 8 qtrs. is too much; I believe it is actual 7.8 qtrs.
The problem besides that slight overfill is that you don't always get all the oil out even when you let it drain for a long time especially if the engine is cold or cool when changed.
What I do now after getting overfill light once when I changed the oil and once when the shop changed the oil; is only put in 7.25 qtrs. and then warm the engine up, check the gauge and add a little at a time. Even then I leave it low until I've really driving the car for a few days to be sure the reading is true.. .
I do the same and slowly "sneak" up on the final fill.
Porsche
makes this task time consuming considering you need to close the hatch and drive the car again after each additional fill otherwise you might be shown the same values as before on the electronic indicator even though you added more oil.
Also keep in mind that you may be looking at liters markers on the bottles and not quarts. For example the Liquid Moly I use comes in 5 liter jugs. You could end up with a half quart overfill situation if you mistake the markers on the jugs as quarts and place 8 in the car. I liter is 1.06 quarts
Thanks, everyone. I appreciate the responses, and I'm relieved to know I probably haven't done anything to damage the engine.
To address some things that were raised:
1. I tend NOT to drive for short spurts. The car is, at the moment, mostly used for commuting, which for me is a 15 - 20 minute drive each way, most of which is on the highway. And even if I take it on a short errand (say for coffee), I'll leave it running while I run in and grab my caffeine, and then I'll extend my drive and try to get it up to normal operating temp for at least 10 minutes. I also try very hard not to take it over 3,000 RPM until the engine has reached temp. That said, there have been a couple occasions this past week where I did take it on short drives and turned off the car before it got up to temp.
2. In the future i will definitely only add 7 - 7.5 quarts to be safe. When I drained the pan this time I actually pulled out the
plug
and then went and blew / raked leaves for like 45 minutes before coming back to the car. By then it was an extremely slow trickle / fast drip, so I figured it was about as drained as it was going to get short of letting it drain overnight.
3. I was definitely looking at the quart ticks, not the liter ticks.
I have to say that while I do love my
Cayman
, the electronic dipstick is annoying. Obviously none of us want to run our engines with too much or too little oil, but in order to check it you have to run the engine for at least a minute or two after the change.I assume
Porsche
has engineered it so that if you put in a tad too little oil it doesn't damage the engine to run it for the minute or so, but I honestly have no idea. Perhaps someone here can chime in on that. (Or you could do a search, Colnago, you dimwit.)
Thanks, again, everyone.
15 minutes will get the coolant up to temp but the oil takes closer to 30 minutes. In the winter, even longer. If
porsche
gave us a decent dashboard you would see that. Since they could not give us oil pressure I guess oil temp would be an extravagance. At least we get 2 speedometers.
