I have an appointment to get the oil re-changed at the same place that did the first one and hopefully document why it had two oil changes in less than a week. They are not admitting that it is even possible they didn't get all the dirty oil out.

They explained the dirty appearance of the extra oil I sucked out by stating that oil often looks dirty right after it is changed, even on a car with 7500 miles just 100 miles after the oil is changed.

Horsefeathers I say.

 

Wow just read this thread, that's terrible. I would not go back to that workshop.

 

I am mostly going back to document what happened

 

Hmmm...3 qts over the top fill line and dirty oil immediately after the change. Pretty obvious what happened here. Did they drain the oil or vacuum the oil?

 

They said they have the extractor and use it. I did not see either way. Tomorrow they said they would put it Ina rack which would be unnecessary with the extractor. So either way I guess is possible. I did not watch.

The only honest mistake that makes sense to me is that they left the filter in and then added 8 quarts and maybe also didn't let it sit long enough before extracting the oil.

The engine was hot when they started the process so he oil should have been easy enough to extract, not that 5-20 is hard to suck out even when cold.

My extractor works on my boat even when cold and I run 15-40 or 20-50 in that.

I would be speculating as to any other possible explanations.

 

Their extraction tube may not have gone to the bottom of the sump. I've never trusted that method of oil extraction. In many engines where the dipstick enters the oil pan is not the deepest section of the pan. The drain plug is always in that location.

 

They just stick the extractor on a pipe provided for that purpose in the fill hole right under the cap

I agree that this factory extraction point may not go to the bottom of the sump but I believe there is a post somewhere in the XK section stating very little oil is left after extraction using the factory extraction tube. Apparently the poster first sucked out the oil, then removed the drain plug to check that out.

I would think an experienced mechanic would know how much oil is left using either drain method and adjust the fill accordingly.

I am still looking for info on how overfilled the thing would have to be to show the overfilled warning, and how much each hash mark represents on the electronic dipstick.

 

If the engine has a built-in extraction tube, the drain plug won't accomplish much more unless the pickup tube was bent. (unlikely).

 

Agreed

 

On my car one scale mark on the electronic dipstick shown in the central Display represents 0.125 l . Checked this by extracting oil with a shot through the extraction tube . So min to max difference is about 1 liter .
Temperature has a big influence on what is shown on the "dipstick" . If engine is hot total oil volume expands about 0.3 l ( assuming 60K and 7 liters ) . So my car shows oil full when hot and approx. 2-3 scale marks missing when cold . Although the oil level sensor is capable to transmit the oil temperature ( see enclosed doc , sorry only got german version ) cars software obviously isn't designed to compensate volumetric oil expansion on the display.

Regards
Ulrich

 

Thanks Ulrich. I can use that information when I see the dealer in the morning.

 

Does this car even have a drain plug?

 

Yes.

 

Although the oil level sensor is capable to transmit the oil temperature ( see enclosed doc , sorry only got german version)

A lot of us would like to have an oil temperature gauge. I wonder if the data from this sensor could be displayed somehow.

 

So I went to the dealer where the overfill occured. I showed them the amount of oil I removed.

I will measure it at a later time before I dispose of it but it was between 2 and 3 quarts. Based on how much we removed today the overfill was between 1 and 2 quarts. So not as bad as it could have been.

The filter looked fairly new so I believe they changed it on the first visit. I suspect the overfill happened because the tech did not watch how much oil was removed before adding oil back in. He probably also did not get all of the oil out based on the color of the oil and how much of an overfill I experienced. I am pretty sure he just stuck 8 quarts in there. There was nothing said about rounding up today.

The oil level sensor does appear to give widely variable results. a dipstick would be much better.

I would try to avoid overfills by making sure the oil level is correct before starting the oil change process, allowing plenty of time for oil to settle after loosening the oil filter housing, and measuring the oil removed.
The dealer's extractor does show how much oil came out. They should be able to put the same amount back in.

I will probably use the drain plug next time as I am not convinced the exractor removes all the oil.

I will say that I was treated better today in person than when I was emailing yesterday to explain the issue.

I am still researching how much extra oil it takes to trigger the overfill warning. I plan to buy a few quarts of oil and test it in the car. The dealer I went to today didn't sell oil unless the customer brings a container.

Thanks to all who posted, Brad

 

The sensor output is a PWM signal, and according to the datasheet the temperature is included in that output to the external controller (steuergerät) I assume that the external controller is included in the kit which is why they specify the voltage 5V or 12V.

But in any case i'm pretty sure you would be able to monitor the oil temperature via the SDD diagnostic system, so it's would also possible to get that signal via OBD2, however you would need to know the PID (which you can get from the SDD) and be able to come up with the formula to get sense out of the signal (someone could do this, i.e. Torque App)

The measuring range of the sensor is -40ºC to +160ºC so can guess that's the range of the PID.

 

I will share that with the various people who have brought it up. There is money to be made on this feature if anyone picks up on it. Thanks again for the timely information this morning. It came in handy at the dealership today.

Kind Regards, Brad