Oil Level Gauge Calibration
 

Reference https://rennlist.com/forums/993-foru...l-level-2.html post #17, and https://rennlist.com/forums/993-foru...oil-level.html post #11.

After reading these two threads with excellent information provided by Mike J, I decided to calibrate the oil tank level sensor on my 993. I wanted to document the changes I did and results noted, so I made a template of stiff wire to follow when making the bends in the float arm, so they would be more precise and could be replicated.

The calculations I made indicated that 2 degrees of bend in the float arm should produce 1mm of change in float level position. I first tried 20 degrees of downward bend, but the results were not satisfactory—not enough change—so I next tried 30 degrees total bend, which should present the float 15mm lower than original stock position.

Note that the float can be withdrawn from the tank by rotating the sensor mounting flange clockwise about 90 degrees. Removal should be done gently with care, so as not to pop the float off the end of the arm.

I did the bending as Mike J described, using two pliers, near the midpoint of the float arm, indicated by the yellow arrow in the picture below.

My goal was to have the gauge indicate half full (needle at 3 o’clock) when the engine temperature is around 200F, and oil on the dipstick measures halfway in the twisted part, engine idling. It appears that 30 degrees of bend in the float arm has done the job.

Thanks for posting this thread. This is on my list.

Did you reuse the gasket behind the mounting flange?
Were you able to do some trial and error without draining oil?

Yes, I reused the gasket, but it was only a year or so old.

And yes, I did some trial and error without draining the oil. This is possible if the oil level is not above halfway on the dipstick, the rear of the car is jacked up, and the car has been sitting overnight.

Interesting

Porsche has through the years, progressively changed material of nuts on several areas of the 993 since production.
One of the parts that changed, are those 6 lever nuts, since the original ones rusted.
If you order six new nuts, they are made of stainless stuff

Thanks, Geolab. One of your posts, along with one from timothymoffat, got me motivated to do the adjustment on the sender, so it shows the level where I want the oil to be in the center of the gauge so I can monitor it.

Originally Posted by timothymoffat: "Everyone here has gone through this with their first (air cooled) 911. Rely mostly on the dipstick and find that "sweet spot" that each car has. I was convinced my 95 was consuming oil until I discovered that it would "use" oil only until a certain level on the stick then not budge, a point which would only register on the gauge in HOT weather or HEAVY traffic."

From Geolab: "THAT IS EXACTLY WHAT EVERYBODY SHOULD DO.
THERE IS A SWEETSPOT, EVERY DROP OF OIL MORE, IS THROWN IN THE INTAKE.
MINE AT THE SWEETSPOT DOES NOT REGISTER ON THE GAUGE AT ALL.
ON THE DIPSTICK, IT IS AT HALF LEVEL. "

The six nuts retaining the sender on my car weren't rusty or corroded, so they may be stainless. Or maybe not, here in SoCal we are blessed with a climate that is kind to cars.

Thanks for the post. I need this done on my car, as the needle doesn't get out of the red zone when oil is at least half way up dipstick. MikeJ mentioned this possibility to me when he changed my oil last August, so I think it is time to have him do it one of these days.

Part number for the gasket? Sorry, I'm lazy

The part number is shown in the first post, in the picture, on the side of the sensor body.

The gasket part number is the only thing I'd need.

Sorry, I misread your post. The gasket is part # 993 207 226 00.

^^^^^ Thank you sir. My next project :-)

I drove the car some today, and was able to confirm that the gauge reads at the midpoint when the dipstick shows halfway. So now the "sweet spot" is when the engine is fully warmed up and the needles (oil temp and oil level) point at each other.

Sounds perfect to me.

Considering the number of SAI issues we read about; it is my belief that, engine oil overfills and a non-functioning SAI check valve, may very well be two contributing factors at the heart of the SAI plugged port issue.