How do I tell if oil is circulating from sump to case?

[H.G.P.]

Is there a way to discern that oil is circulating from the sump to the case?

Thanks

[Formerly Steve Wilkinson]

Do you mean from the tank to the case? The sump is the bottom of the crankcase, which in the case of a 911 is "dry"--i.e. doesn't collect oil as a conventional engine's sump does--so there's not much point in checking that the oil is circulating from the sump to the case.

If you mean from the tank to the case, just check, with your hand, that the tank in the fender well is hot after running the car awhile. If it is, the oil has visited the crankcase.

Of course, this is all moot. If your engine continues to run, the oil is circulating correctly.

Stephan

[H.G.P.]

Yes, I mean from tank to case. Is it possible that the tank could just feel warm due to the proximity to the case, and the oil not be circulating?

[APKhaos]

There will be other more spendy symptoms if the oil is not circulating properly. This is a very high flow rate oiling system. The time of operation between an oiling system failure and engine destruction is very short.

What symptoms are you observing that leads you to ask this question?

[H.G.P.]

I have no symptoms at all, the car is running great. (The temp gauge stays usually below 180, although that oil level arrow fluctuates, and stays rather low, even after a fresh oil change!)

[APKhaos]

Don't trust the oil gauge - they were innacurate when new, so its highly possible that your 33 year old sender is providing bogus information. The gauge is completely unreliable under anything other than car motionless, engine running, level ground conditions - even when the sender and gauge are perfect. Cunning German design specs.

Check the oil with the dipstick; engine warm and running, parked on level ground. Fill level is the mid point between the two marks on the dipstick. More is NOT better. Too much will lead to ingestion of oil into the induction system, with consequences.

[Formerly Steve Wilkinson]

H.G.P.'s questions involve oil circulation, not oil level. I suspect his oil-level gauge is working just fine, just as all of them typically do--i.e. fluctuating confusingly and wildly while driving, etc.--but that's not the point. Obviously, his oil circulation is normal. (H.G.P., your oil tank will _not_ get warm simply as a result of proximity to the engine. In the first place, it isn't that proximate, and in the second, it'll be cooled a certain amount in any case by airflow through the fenderwell. So if it's warm, you're cool.)

I don't know why people keep criticizing the 911 oil-level gauge as being "inaccurate when new" and "providing bogus information." The gauge has only one function: to read out oil level after the engine is warm, with the car idling for one minute on a level surface. At any other time, the gauge is "inaccurate" and "bogus" simply because it is operating in a realm for which it was not intended. For people who don't understand this, it would probably have been better if Porsche had fitted a sensor thqat simply disabled the gauge as soon as the car sensed forward motion. But then Porsche foolishly assumed that owners would RTFM.

Stephan

[APKhaos]

Had a bad day, Stephan?

Read back a post or two and you may see that we had covered the circulation issue. HD had then asked a follow-up question on the gauge/tank level issue.

My point was that a 30+ YO sender is not to be relied upon. In fact, best to ignore the gauge and rely solely on the dip stick. Your defensive rant notwithstanding, I find that to be more valuable advice for new owners than to confuse them with the specific set of conditions under which the gauge MAY give them a rough indication of the real level in the tank [given that the decades old sender and gauge are still within spec].

You are free to take your own road on this, of course. I will repentently read my user manual and seek salvation in its wisdom.

[CamB]

The gauge has only one function: to read out oil level after the engine is warm, with the car idling for one minute on a level surface.

I agree - mine is 100% accurate in this scenario.

[Paul Thomas]

What is RTFM?

Cam, did you get the article i emailed?

Paul

[CamB]

Yes! Thanks! I thought I replied with the same (thanks).

RTFM means Read the F****** Manual

[APKhaos]

RTFM = Read The F***ing Manual!

Has is origins way back in WW2, when the broadscale application of new technology swept the industrialized world. It kinda helped that the aforesaid industrialized world was arranged into two teams, each one hell bent on the destruction of the other.

[H.G.P.]

The gauge has only one function: to read out oil level after the engine is warm, with the car idling for one minute on a level surface.

How warm?

(When I initially turn the ignition on the level gauge needle jumps right above the red mark. Then it falls into the red zone UNTIL I drive the car for quite some time before the needle begins to move up, usually to the mid point on the gauge)

[CamB]

Operating temp - 180 deg or so. Mid point of gauge range should be about mid way on dipstick and about perfect.

[H.G.P.]

Originally posted by CamB
Operating temp - 180 deg or so. Mid point of gauge range should be about mid way on dipstick and about perfect.

OK..Thanks.......Operating temp today never got close to 180, despite a short highway drive. So the needle did not move but very slightly above the red mark, and when the car was at a standstill. I did check the dipstick immediately after driving, and the level was mid way. Thanks again.

[CamB]

Over the red mark is prob pretty much warm enough, in my (actually fairly minimal) experience.

[H.G.P.]

No, not the temp red mark, the oil level red mark. Never got above the low LEVEL red mark.