oil separator symptoms

[MisterKenJ]

I've read quite a few posts about the oil separator problem, but I've not seen any information about whether or not this can occur on a diesel.

Just yesterday I bought a 2010 X5 xDrive35D, and it will be delivered next month. We live in Utah, and have a heated garage, but it sometimes gets pretty cold here. Rarely below 10 F, but sometimes below 0 F. Our shortest drive would be 15 minutes or so one way, down, then up the mountain.

So, is the diesel engine subject to the OS problem? Will the sort of driving we do ... perhaps to go out for dinner on a cold night ... be a problem?

Thanks ... and wish me luck with my new car!

[JCL]

While a diesel requires a crankcase ventilation system the same as a petrol engine does, I have no idea if the new BMW diesels are using anything similar in design to the traditional oil separator valve that is discussed above. It doesn't show up in the Realoem parts catalogue, but that may be due to changes in the catalogue as much as changes in design.

I wouldn't spend much time worrying about it, enjoy your new car. If you do a lot of short trips, you may see some accumulated paste under the oil filler cap, and if so that indicates that the engine isn't getting hot enough to burn off the condensation. That is a better thing to check in my opinion than trying to chase down a problem that may not even exist.

[MisterKenJ]

Thanks! Sounds like good advice!

[dinan6]

I live in fairly cold country (Northern NV) and am planning to purchase a used 2002 or 2003 X5 with the 4.4 V8 engine. Since this car may spend a number of nights outside in the winter cold, is there a certain low temperature at which I should retrofit the engine with the insulated Oil Separator and the electric heat blanket? It's sort of a pricey and Rube Goldberg retrofit, so I don't want to do it unless the mod kit is really needed.

For example, are the improved parts needed with night time lows of 20F? What about 5F or 10F or 15F? We regularly see winter night time lows in the teens around here. I had an experienced mechanic around here tell me that he didn't think the improved parts were needed, but the last time I checked, a car sitting outside and not operated for several days will get pretty cold, especially if daytime temps stay below freezing. So I am leery of blindly following his advice. What is the experience and recommendations of the forum members on this subject (for the nighttime temps I have noted above)? Thanks.

[JCL]

Originally Posted by dinan6

I live in fairly cold country (Northern NV) and am planning to purchase a used 2002 or 2003 X5 with the 4.4 V8 engine. Since this car may spend a number of nights outside in the winter cold, is there a certain low temperature at which I should retrofit the engine with the insulated Oil Separator and the electric heat blanket?

For example, are the improved parts needed with night time lows of 20F? What about 5F or 10F or 15F?

The real questions are (1) has the oil separator ever been serviced on this used vehicle? and (2) are you planning to do lots of short trips that don't allow the engine to warm up fully? The separator isn't the issue, and the cold ambients are only a contributor, not the cause. See post #32 in this thread for more details. It isn't a case of a temperature threshold as much as it is a case of allowing the engine to warm up completely and burn the condensation off. If you do that, there won't be much in the separator to ever freeze up, no matter what the temperature is.

In terms of cold start capability, I didn't have problems with my 3.0 parked outside occasionally in -20C to -30C. No external heat source. As soon as I had a stable idle speed I would drive it (gently) so that it warmed up as quickly as possible. Nothing worse than leaving it idling with no load.

[dinan6]

JCL,

Thanks for your informative response. One of the reasons that I am concerned about the 4.4 engine in my environment is that I will be doing a likely mix of 3-5 short trips (2-5 miles in length) for every 60 mile trip that I take. Because of the heavy expense that can occur if the crankcase ventilation system freezes up, I will definitely be taking the beast apart and cleaning it up and replacing hoses/parts as soon as I purchase the new-to-me vehicle. I guess it might be advisable to do this inspection/cleaning twice a season in the winter.

My V8 Jeep is not nearly as sophisticated as the BMW in a number of ways, but at least I don't have to worry a bit about its crankcase ventilation packing up and taking the engine with it... I think I am still going to get the X5, though.

I've done quite a bit of research on this site concerning failure modes and the consequences of a frozen oil/water separator. It does seem to be a pretty serious problem that BMW could have done a better job in solving. Where was their long term cold weather testing program prior to entering production? Are there any home-engineered solutions that will keep these ventilation lines freeze-free in short mileage driving scenarios?

[Wilk]

Left my '01 4.4 outside my warm garage (mistake) so we could have a new years party. started it up at -5 F and drove it about 5 miles realized I was one of those idiots leaving a giant smoke screen behind me. I usually laugh at those people cuz they dont know something is wrong.
my X has 113K on it, bought with 100K. After I had my wife pull me home with my trusty steed Yukon I pulled the oil seperator out, blew it out and there appears to be all new hoses, new osv and has an electric warming blanket around the hoses. It appears that the extra winter kit doesnt help all that much. I took the throttle body off and stuck some rags down in the intake and got a lot of milky oil out of there.
after running it for half hour it appears cleared up, must have been lots of oil in the exhaust. I ran it for 5 minutes the first time and took throttle body off to check for more oil, which there was a little, but not much. Decided to run it longer the second time and checked again. Looked good after that check.
I dont get it, do I have to drive something else when it gets really cold out. My wife had parked it after a one hour drive, shouldnt have been a big problem with condensation.
I thought some of you might be interested to know that the extra money spent on the cold weather parts dont really seem to completely fix the problem, although they may help, who knows.
The X normally gets drive 25 minutes to and from work on a very regular basis. If it wasnt so awesome in snow, which we have a lot of, I would get rid of it. I called the local dealer and spoke with a tech who was very helpful, he said if all those parts look new to just blow it out and reuse it.
In the 6 months I have had it I was stranded by an alternator (trans fail safe warned me a couple times), tailight problems, display issues on radio, now the OSV. Its going to be a long winter.
Thanks to this site I am able to figure these issues out. Fantastic information on here and I dont know what I would do without it.

[JCL]

Wilk:

Good diagnosis, and exactly the right course of action, IMO. You are right that the new parts don't fix the problem, they just raise the threshold somewhat. Unless you know the history before you bought it, the condensation could have been building for a while. Check it every year, clean it out if necessary, and you should be fine.

Glad the site is helpful.

[dinan6]

Wilk,

Thanks for sharing your not so wonderful experience with the Oil Separator Modification Kit. Driving for an hour should certainly help to get the water out of the oil, unless your thermostat is not working correctly and the engine is running too cold in the winter.

It's beginning to sound like X5 owners in cold climates need to pull their engine oil caps and look for moisture buildup inside the caps with just about every gas fill up during the winter months. Hopefully someone has developed or will develop a better fix than the factory's marginal approach to this condensation problem.

[rocky1536]

Originally Posted by juppalgae

12-21-2009, 03:47 PM

“i was just told by a professional that the oil separator for e53(os and its hoses) is same as e46. pls, advise.”

12-21-2009, 07:41 PM

“i was just told by a professional that the oil separator for e53(os and its hoses) is same as e46. pls, advise.”

12-21-2009, 09:39 PM

“i was just told by a professional that the oil separator for e53(os and its hoses) is same as e46. pls, advise.”

12-22-2009, 01:13 PM

“i was just told by a professional that the oil separator for e53(os and its hoses) is same as e46. pls, advise.”

Are you serious?

You take annoying to a whole new level...I'm sorry.