E39 530d Oil Level Puzzle
Discussion
I was always told to check oil level when the engine is cold, that way the oil in the engine can drain down and you get an accurate reading on the dip stick. I have always found it difficult to get similar consecutive readings despite wiping the stick etc etc so today I decided to look more carefully.
First check was after the engine had stood for several hours, and the reading was below the low mark. Ran the engine for several minutes, wiped carefully and checked again and got a reading between low and high. I should have thought that running the engine would have produced a lower reading than before as some oil would still be in the top of the engine and other places above the sump.
So can one of you very clever gents explain why an engine that has drained it's oil down into the sump for hours shows less on the dipstick than one that has just pumped it's oil out of the sump and around the houses!!
First check was after the engine had stood for several hours, and the reading was below the low mark. Ran the engine for several minutes, wiped carefully and checked again and got a reading between low and high. I should have thought that running the engine would have produced a lower reading than before as some oil would still be in the top of the engine and other places above the sump.
So can one of you very clever gents explain why an engine that has drained it's oil down into the sump for hours shows less on the dipstick than one that has just pumped it's oil out of the sump and around the houses!!
There are potentially many reasons & which (if any of these) is applicable to your car will take some more investigation by you.
1. "The laws of physics apply" - As in when you warm something up it expands, whether this would be enough is debatable.
2. When the dipstick is brought out (quite often round some quite severe bends in the dipstick tube) there is still oil running down from the head & this is being caught by the dipstick.
3. If you have diesel being washed though the engine it will raise the level.
The likelihood with yours is something like 2 as the e39 I used to have was like this & I always used to have to do a few "dips" in order to get something like a consensus.
The R53 mini I currently have has 2 ridiculously tight 90 degree bends (causing most dipsticks to break) and it is virtually impossible to get a good consistent reading.
1. "The laws of physics apply" - As in when you warm something up it expands, whether this would be enough is debatable.
2. When the dipstick is brought out (quite often round some quite severe bends in the dipstick tube) there is still oil running down from the head & this is being caught by the dipstick.
3. If you have diesel being washed though the engine it will raise the level.
The likelihood with yours is something like 2 as the e39 I used to have was like this & I always used to have to do a few "dips" in order to get something like a consensus.
The R53 mini I currently have has 2 ridiculously tight 90 degree bends (causing most dipsticks to break) and it is virtually impossible to get a good consistent reading.
E-bmw said:
There are potentially many reasons & which (if any of these) is applicable to your car will take some more investigation by you.
1. "The laws of physics apply" - As in when you warm something up it expands, whether this would be enough is debatable.
2. When the dipstick is brought out (quite often round some quite severe bends in the dipstick tube) there is still oil running down from the head & this is being caught by the dipstick.
3. If you have diesel being washed though the engine it will raise the level.
The likelihood with yours is something like 2 as the e39 I used to have was like this & I always used to have to do a few "dips" in order to get something like a consensus.
The R53 mini I currently have has 2 ridiculously tight 90 degree bends (causing most dipsticks to break) and it is virtually impossible to get a good consistent reading.
Thanks for your suggestions, much appreciated. I have already thought about, and discounted, ! and 2 because, in the case of I the difference on the dip stick must at least equal half a litres worth of expansion and that just cannot be possible by only warming the engine. In the case of 2 the dipstick tube is not excessively bent and I have taken great care to wipe the stick carefully to avoid leaving excessive quantities of oil in the tube. I feel 3 is unlikely because the engine does seem to use some oil so there is net consumption of oil and also I can get three different levels by dipping three times in as many minutes - which points to 2...………….. Ah well, another eight years of pondering may reveal the answer! ..1. "The laws of physics apply" - As in when you warm something up it expands, whether this would be enough is debatable.
2. When the dipstick is brought out (quite often round some quite severe bends in the dipstick tube) there is still oil running down from the head & this is being caught by the dipstick.
3. If you have diesel being washed though the engine it will raise the level.
The likelihood with yours is something like 2 as the e39 I used to have was like this & I always used to have to do a few "dips" in order to get something like a consensus.
The R53 mini I currently have has 2 ridiculously tight 90 degree bends (causing most dipsticks to break) and it is virtually impossible to get a good consistent reading.
Gassing Station | BMW General | Top of Page | What's New | My Stuff