Nutbeem

I had my oil changed along with my 60k service at 58,800 miles a few months ago. I just hit 61,000 yesterday, so I thought I would top off the oil - the sucker took 4 quarts of German synthetic oil for 2200 miles - geeze.

I have NO oil leaks (not a drop), nor do I have any visible smoke - engine runs great and strong.

My mechanic says not to worry - "911's burn oil!", but as I said in another thread this week, I live in constant fear of the rebuild.

Any thoughts? Any similar situations?

Eric Kessel

Did you check the level after the last oil change? And, how did you check it this time? Is there anything built up on the inside of the tail pipe?

If it's really 1qt/500 miles, you should see some smoke....... either at startup, or maybe when decelerating in gear...........
-Eric
90 C2

Steve Weiner-Rennsport Systems

Hi Rick:

LOL,..there might be more to this story than meets the eye, but are you saying that your engine used 4 qts of oil in 2200 miles?

May I offer some suggestions?

1) First, establish a good accurate baseline of current oil consumption. Set the oil level at 1/2 level on the dipstick (when all warmed up) and note the odometer. Check the level again every 500 miles and keep a log of how much you add every 500 miles.

2) Have a leakdown test performed and have the source noted on any leakage found.

3) Finally, if your oil consumption is more than 1 qt per thousand miles, then have the lower valve covers removed and the exhaust valve guides checked for side play. Done properly, this will indicate the level of guide wear.

FWIW, a normal, healthy 911 motor uses about 1 qt per 2k miles under normal driving conditions.

Nutbeem

Thanks for the replys - Ever since I got the car it's been about 1 quart per 800-1000 miles, but this time it seems worse.

I'll benchmark it for a while and see where I'm at, and I'll get the leakdown test performed.

JasonAndreas

Please don't take this the wrong way but what was the oil temperature at when you added fresh oil? How long had you been driving or idling the motor before you added oil?

Nutbeem

No offense taken - oil temp was between 8:00 and 9:00 - it was a hot day today, and I took a spirited drive on my way home from work.

My driveway is nice and flat, and since I can't seem to get a decent reading from the dipstick, I used the guage. When I had the oil changed, the guage read about half full. I took a thousand mile round trip to Monterey in January, an LA Porsche run for about 250, and then mostly short spirited drives around town since then.

I've always worried about the oil consumption - It seemed to use too much too fast, but there were no other symptoms that I could find that would explain. Pretty young motor, runs great, no smoke.

It's like when I was diagnosed with high blood pressure at 33 - pretty young motor (heart), runs great (not as great as it used to), non smoker.

Now I can't wait to get this thing tested. I think I'll take it to a specialist, rather than my local guy...

tierraman

Rik: My 964 seems to use more oil in stop and go traffic (1qt/1,000-1500 mi) and uses vurtually no oil on the highway. I'm sure all our gauges are a bit different, but mine reads about 1/3 to 1/2 at hot idle when I'm 1-1.5 qt below full. Also, FYI, cars with cat converters will not smoke with minor oil consumption.

Adrian

Dear Rick,
I think you will have to establish a benchmark first. The problem is you do not know if the people that did your service put enough oil in. You might have to consider investing some money to find piece of mind.
I would recommend you have the oil drained from the engine again but this time measure how much is removed. If done properly it should be around 8 to 9 litres.
You then put back in exactly the same amount that you removed. Warm the engine up etc and then check the dipstick and mark the oil level. Do the same with oil level indicator inside.
These are your benchmark levels. Then check your oil consumption from these marks.
Ciao,
Adrian
964C4

eddychan

I think Joe is right. In my experience, I do a lot of motorway milage and my oil consumption is very low.
My mechanic told me to check my oil level after warming up the engine to 9 o'clock not between 8 and 9 o'clock. So bench marking and use a consistent and reliable method to check the oil level is the only way that you can be sure about the consumption.
Do you detect any smoke from the exhaust?
I also assume that there is no oil leakage.
Best of Luck.

Eddie
91 C-2

Nutbeem

I was so concerned I had a leakdown/compression test done, which came out great. I had them drain the oil, and put a thicker synthetic - I've put a few hundred miles on in the last week, and the guage doesn't seem to be down at all.

The car is running so good I can't fathom that there is a major problem...

Flying Finn

Here's another oil consumption dilemma:

My car, as Joe's & Eddies consumes oil when idling (i.e. stop & go traffic) and basically nothing when driving hard.

When I sit in a S & G traffic, I can see little smoke coming from right exhaust (I have removed the cats, before I saw nothing) and will notice higher oil consumption. Yet, when I go to the track, car doeasn't smoke at all (and consumption is down) and actually after a good hard day at the track, even sitting in traffic doesn't start the usual little smoking.

My car's oil consumption is not that high (one quart / 2000 miles) but this smoking thing buzzles me, I can't figure out why it only consumes when driving in traffic.

Any ideas?

I guess it's just meant for real driving, not pussyfootin' around town.
Good thing most of my driving is real driving!

914und993

When idling, manifold air pressure is very low which increases the pressure differential that will drive oil past worn valve guides. Decelerating in gear will do the same thing.

Chip

joey bagadonuts

Not sure if this was really clarified but it is possible to overfill the oil tank. Rick, how do you determine when it's full? If your gauge shows full all the time then you've overdone it. Very easy to do.

If you're not adept at using the dipstick (which isn't as simple as it sounds) keep in mind that the oil level needle shouldn't move until the car is warmed up. When your car is fully warm (8 o'clock), idling and on level ground, it will tell you how you're doing.

Forgive me if this is obvious but all the gauge tells you is whether the car's been properly topped off. Basically, it represents the last quart added to the tank. When it stops moving, then add another quart. Remember, there's still about 11 quarts running through the system so it's not a problem to let it run down.

eddychan

A bit of white smoke in the morning when the engine is cold is quite common, you only notice it when you stop in the traffic, it should go away when the engine warm up.
Blue/cloudy smoke indicates worn or overfilled oil, it is quite easy to overfill and you should check carefully.
Joey, my mechanic who has been working for Porsche over 25 years told me to wait till 9 o'clock, may be he is just too carefully. He told me to get to 9 o'clock and the oil guage should be 3 o'clcok.
Nine and Three should make it right, he told me.
Would like to hear some comment on this!

Eddie

JasonAndreas