oil level problem

einreb92 · 02-02-2009, 12:51 PM

Ok. Maybe I'm not the sharpest pencil in the box but it was bothering me that the oil guage in the small cluster to the left was resting on the red hash mark, so I decided to check the oil via the dip stick. It looked a bit low and didn't look exactly like the picture in the book. I slowly added oil and looked through the back window and saw the needle went to the horizontal position after I added about 3/4 of a quart. I checked the stick again (all while the car was warm and running) and it was at the top of the twisted section. "Great. My first DIY," I thought.

I got about a mile from my house and smoke began to pour out of the rear. I don't know what if any damage I've done but more curious is the fact the after 10 miles or so of "burning off the extra," the needle went back to the bottom position. The pressure is great on the other oil dial but I don't know if I have a problem that needs to be addressed. Any help on this one?
Thanks in advance
Bernie

kurquhart · 02-02-2009, 03:49 PM

I doubt you over filled it by adding 0.75 quart. Did you by chance spill some oil down on the exhaust?

I can't tell from your description if you know this, but just in case: the oil level gauge should appear low when driving; the level (gauge or stick) is only meaningful after idling hot and level for a few minutes.

einreb92 · 02-02-2009, 05:18 PM

No. I used a funnel. The car was level etc. Still the smoke poured out for miles.

38D · 02-02-2009, 05:31 PM

You overfilled it...no biggie. The gauge is worthless...use the dipstick.

Britwrench · 02-03-2009, 08:33 AM

The oil level gauge works fine, yet to see any problems with it. Have worked on 964 since introduction.

Always check with engine hot (rest hand on right front fender to check oil cooler thermostat has opened), idling and allow a little time for the oil to settle. Run the level at about 3.00 o'clock on the guage.

ischmitz · ischmitz's Garage

Bernie,

The important thing is to measure the oil with the engine fully warmed up. The oil areats and expands with temperature - both increases the volume. That's why you need to drive the car and get the engine to operating temperature before taking a reading. Next measure the level with the dipstick and have it centered between the low and the high mark.

Then you can look at the oil level gauge - it's reading now corresponds to a healthy oil level. Familiarize yourself with the oil level gauge. When you add a quart on mine it sends the needle into its upper maximum. When it is low on oil the needs won't even make it out of the red unless under heavy breaking. So I have a pretty good feeling for what the gauge says and what it corresponds to on the dipstick.

On mine (Early 911 oil tank) it is the 2 o'clock position that matches the half mark on the dipstick. This can vary from car to car. I usually check my level by coming to a full stop on level ground and watching the oil gauge after idling for a minute. Every once in a while I use the dip stick to make sure.

If you overfill the oil it will get ingested into the engin through the intake once the car warms up. While the smoke is anoying and embarassing the real danger is that oil in the intake charge dramatically lowers the knock-resistance. It's like having fuel with a knock rating of 80. The resulting knocking can cause real damage to bearings, rings, ring lands, etc. So it is best to avoid this.

Cheers,
Ingo