403portside

Hi folks,

Pardon my ignorance here.

I got my oil changed last week. Prior to that my oil level read at the top bar or sometimes one level below. After the oil change it reads a bit lower but still between the two arrows.

Does this mean perhaps that previously my oil was a bit overfilled and can I trust that I have the right amount of oil now? Should I just add more or could I then be overfilling?

And yes I'm sure DIY would eliminate the guesswork but it's not an option for me.

Thanks in advance.

Mike in CA

Regardless of where your oil is after the change, the top line marked by the arrow indicates a full oil level. If you are below that mark your oil was slightly underfilled when they did the service. Not saying that it is necessarily harmful, as long as you are a segment or two above the bottom arrow, but you are not full.

Each segment between the arrows is approximately .42 quarts, so the total volume between the top arrow and bottom arrow is approximately 1.3 quarts. To bring your oil level to maximum, add .4 quarts for each segment that you are below the top line.

BTW, all of this is in the manual.

ADias

You are probably a fraction of a quart under-filled. Either leave it that way, or add just a tiny bit - 1/8 of a quart and re-check. Do not overfill!

Edgy01

Here at Rennlist we hear more about overfills at dealers so I would say you're in a better position. I have found that the quantity of oil between max and min is roughly 1 litre, so simply add a quarter of a quart and see how that settles things. If you need to, simply top it off a bit more.

403portside

Thanks gents!

ray09c2s

My dealer checked my oil level after I ran one DE event; had just changed oil before I went, and it was a bit low also; they just topped off for me. As was noted above, the tech rep said it's not unusual for it to be a bit off after a change, and they don't mind correcting....better low than high!

Macster

As long as the oil level is not above the max. line, the segment above the max line is not lit, the engine is not overfilled with oil.

Now after having torn into an oil level sensor I can understand a bit about the caution regarding overfilling an engine with oil. The oil level sensor doesn't have the ability to report how much oil over the max. line level there is, so one can't know if the engine has just a fraction of a quart too much oil or much more than that.

I would prefer to operate the engine with the oil level at least a few bars above the low level line.

When I change my cars' oil I refill the engine or oil tank to bring the oil level up to 2 or 1 bar below the max line. When I have the oil changed at the dealer this is how much oil the techs fill the engine with as well.

I prefer to operate the engine with the oil level closer to the max line (but not over it!) than closer to the min line.

I would never run the oil level down so low as to cause the low oil level warning to come on.

In fact, I have always made it a rule that whenever the oil level drops to halfway between the max and min level lines that this is the time I add enough oil to bring the oil level back up to within a line or two of the max. level line.

Sincerely,

Macster.

Minok

its the same as with the dipstick. You have range on a dipstick thats the valid zone of fill level. The fill after an oil change can end up anywhere in that range... none is better than another.

Personally, I don't shoot for the top but the middle... so you have a bit of space and less likely to overfill.

Macster

You are not changing the oil right, that is you are not taking advantage of the oil change procedure to verify the electronic oil level system is working properly.

While I do not have the factory oil change instructions/steps for the 997 engines, I suspect the instructions are similar for these engines as for the earlier engines, the M96 engines in the Boxster, 911 and even the Turbo cars.

For the 996 engines the general oil fill instructions call for a specific amount of oil to be added to the engine and the oil level indicator should have a specific number of segments lit.

For instance, for the 996 Turbo the engine is brought up to operating temp (there is a specific temp callout given in the factory manual in the oil change section but I forget what it is) and the oil drained for 20 minutes.

Afterwards, 7.8l of oil is added to the oil tank and the oil level checked with the electronic oil level system. 7 segments should be lit which puts the oil level at the max line.

This provides the tech performing the oil change a chance to verify the electronic oil level system is working properly.

I asked a tech what is the allowed variation was, how many segments below this or above (there's only one segment above the max line) the reading could be and the electronic oil level system still be considered functioning properly and he told me he's never seen a display read different from what the factory says it should. In one case the level wasn't displayed at all and the oil level sensor/sender was replaced.

Sincerely,

Macster.

Minok

Thanks for that tip. I'll do that the next time. Wonderfull that we have to do more detailed oil changes to compensate for an oil level system I suspect many of us would just as well do without.

My oil changes are: engine warm, drain the oil... let it drain for 20-30 mins, change filter, add known quantity of oil to the engine, let it settle in, warm the engine, read the level. I'm putting in a fixed amount.. not an unknown amount, so if the sensor was way broken, I'd notice, but not if it was only 'slightly off'.

So whats the 997.2 3.6L magic oil quantity to add to what specific mark? That info should be in the manual, if you ask me.

Macster

Well, I may be in the minority but I love the electronic oil level check/display system. Both my Boxster and Turbo have it and the car in between (not counting the short-lived Cayman S) a 2006 GTO had the old dipstick and if felt particularly medieval to have to check the oil level by getting out of the car raising the hood and pulling some dipstick out of the engine and you know the rest.

To me it is a small price to pay to have to go through a bit more complex oil change procedure to verify the electronic oil level system is working ok.

As for your question: The magic oil quantity for the 997.2 3.6l engine? I do not know the answer.

I do know Porsche is darn tight-lipped about these things though so that it is not in the owners manual makes sense (knowing Porsche).

But you might get this info from your local Porsche dealership service department, from one of the senior techs you've built up a relationship with.

Again I'm probably in the minority but I find the techs at my local dealer, in fact several dealers I use, quite helpful provided I keep in mind they're on the clock and often under time pressure and too busy to take time to answer my questions. But all 3 techs at my dealer have shared with me info regarding my car and sometimes other models that I have asked about.

Sincerely,

Macster.

Minok

Well if Porsche won't share, then I'm changing my oil correctly. Oil changes are certainly something the owners are expected to be able to do, and if the manufacturer isn't providing the data to do it right, then maybe the electronic level system really is not the right solution.