If this is your first visit, be sure to check out the FAQ by clicking the link above. You may have to register before you can post: click the register link above to proceed. To start viewing messages, select the forum that you want to visit from the selection below. |
|
|
Thread Tools | Display Modes |
#1
|
|||
|
|||
Synthetic and oil level reading
Since I filled my 1991, 750iL with Mobil 1, 0W-40, the low oil level
alarm has started going off when the (overnight) dipstick level is 1/4 of the way down from the high mark. I have heard that synthetic oil "clings to the surfaces", and thus takes longer time draining to the oil pan compared to conventional oil, and this seems like a confirmation of that. It probably takes 6 hours to get a repeatable oil level reading, prior to that, the level slowly increases. Has anybody else seen this, and if it is true that synthetic oil drains down slower, would the optimal oil level be higher than for conventional oil, or would the risk of overpressure exist during startup? Jan Fure |
Ads |
#2
|
|||
|
|||
I have never heard that synthetic "clings to surfaces" and takes longer
to drain but I do know that synthetic oil will sneak past worn gaskets or valves much faster than conventional oil, which is why I didn't change to synthetic on my 150k 525i. In my experience, synthetic flows quite rapidly especially in cold weather. - Scott "Jan Fure" > wrote in oups.com: > Since I filled my 1991, 750iL with Mobil 1, 0W-40, the low oil level > alarm has started going off when the (overnight) dipstick level is 1/4 > of the way down from the high mark. > > I have heard that synthetic oil "clings to the surfaces", and thus > takes longer time draining to the oil pan compared to conventional > oil, and this seems like a confirmation of that. It probably takes 6 > hours to get a repeatable oil level reading, prior to that, the level > slowly increases. > > Has anybody else seen this, and if it is true that synthetic oil > drains down slower, would the optimal oil level be higher than for > conventional oil, or would the risk of overpressure exist during > startup? > > Jan Fure > > |
#3
|
|||
|
|||
"Jan Fure" > wrote in message oups.com... > Since I filled my 1991, 750iL with Mobil 1, 0W-40, the low oil level > alarm has started going off when the (overnight) dipstick level is 1/4 > of the way down from the high mark. > > I have heard that synthetic oil "clings to the surfaces", and thus > takes longer time draining to the oil pan compared to conventional oil, > and this seems like a confirmation of that. It probably takes 6 hours > to get a repeatable oil level reading, prior to that, the level slowly > increases. > > Has anybody else seen this, and if it is true that synthetic oil drains > down slower, would the optimal oil level be higher than for > conventional oil, or would the risk of overpressure exist during > startup? > I think you read too much science fiction. Huw |
#4
|
|||
|
|||
Scott wrote:
> I have never heard that synthetic "clings to surfaces" and takes longer > to drain but I do know that synthetic oil will sneak past worn gaskets > or valves much faster than conventional oil, which is why I didn't > change to synthetic on my 150k 525i. In my experience, synthetic flows > quite rapidly especially in cold weather. > > - Scott This is an urban legend, IMO. A synthetic maintains viscosity closer to its rated value(s) over the lifetime of the oil. There is no reason to believe it will leak past gaskets more than a thinned out dino juice. The only *possible* reason for this oft quoted legend would be that the superior cleaning properties of the synthetic may actually disolve some of the gook that has built up inside a higher mileage engine previously subjected to only cheap oil. That gook could be sealing your dried out and leaky gaskets, but I have never experienced this phenomenon and I've switched several high mileage cars (over 100k miles) over to full synthetic with no leaks or increased consumption. -Fred W |
Thread Tools | |
Display Modes | |
|
|