Thanks for nothing BMW NA ( Blue smoke/Oil loss/Oil separator )

[vinuneuro]

It seems to be a problem in vehicles with greater miles, 50k+. It's an issue in vehicles that make short trips, and not getting the engine to operating temperature.

[nrgetic99]

Originally Posted by vinuneuro

It seems to be a problem in vehicles with greater miles, 50k+. It's an issue in vehicles that make short trips, and not getting the engine to operating temperature.

Thats an oversimplification. I will copy and paste the text from the Service Bulletin later on...

David

[JCL]

Originally Posted by nrgetic99

Thats an oversimplification. I will copy and paste the text from the Service Bulletin later on...

David

I don't think that is an oversimplification. Yes, these vehicles can have this problem. Yours didn't. You have assumed that a stumble on idle one time was caused by a frozen separator when in fact it may not have been.

You speak about the production window as if it applies to 2003 vehicles. It is a ten year problem, BMWs have had this issue for that long. Yours is no more likely to have the problem than any other year, or than many other makes of vehicles that use similar crankcase vents.

I wouldn't put the heated lines on, simply because it can fail with them; they aren't a sure fix. They simply decrease the odds of it happening if your vehicle is predisposed to freezing up. That predisposition starts with many short trips and condensation in the separator, it doesn't start with leaving it parked in the cold. If you do a lot of very short trips, then yes, consider the heated lines as insurance. Apart from the lines, however, the best thing you can do is move to an extreme service interval for oil changes, every 7500 or even every 5000 if you want to triple the manufacturer recommendation. Check for signs of water in the oil around the oil filler cap (a white paste). It may be worth having the separator/crankcase vent cleaned out or changed, without going to the heated hoses (they aren't putting any heat down when you start it and it is very cold, and so wouldn't have impacted your stumble if in fact it was caused by a frozen separator).

You imply that it is a sure bet that your engine will eventually fail. Statistics don't support that conclusion. Hundreds may fail eventually. Many thousands have been built. The ones that failed had a heavy buildup of moisture in the lines over time. It is a simple actuarial calculation, nothing more. You can bet that BMW is far ahead by waiting until some fail. Your best bet to ensure you don't get stranded is simply to maintain the vehicle properly, and more frequently given the extreme conditions.

[nrgetic99]

Originally Posted by JCL

I don't think that is an oversimplification. Yes, these vehicles can have this problem. Yours didn't. You have assumed that a stumble on idle one time was caused by a frozen separator when in fact it may not have been.

You speak about the production window as if it applies to 2003 vehicles. It is a ten year problem, BMWs have had this issue for that long. Yours is no more likely to have the problem than any other year, or than many other makes of vehicles that use similar crankcase vents.

I wouldn't put the heated lines on, simply because it can fail with them; they aren't a sure fix. They simply decrease the odds of it happening if your vehicle is predisposed to freezing up. That predisposition starts with many short trips and condensation in the separator, it doesn't start with leaving it parked in the cold. If you do a lot of very short trips, then yes, consider the heated lines as insurance. Apart from the lines, however, the best thing you can do is move to an extreme service interval for oil changes, every 7500 or even every 5000 if you want to triple the manufacturer recommendation. Check for signs of water in the oil around the oil filler cap (a white paste). It may be worth having the separator/crankcase vent cleaned out or changed, without going to the heated hoses (they aren't putting any heat down when you start it and it is very cold, and so wouldn't have impacted your stumble if in fact it was caused by a frozen separator).

You imply that it is a sure bet that your engine will eventually fail. Statistics don't support that conclusion. Hundreds may fail eventually. Many thousands have been built. The ones that failed had a heavy buildup of moisture in the lines over time. It is a simple actuarial calculation, nothing more. You can bet that BMW is far ahead by waiting until some fail. Your best bet to ensure you don't get stranded is simply to maintain the vehicle properly, and more frequently given the extreme conditions.

Whether it has this problem or not, I think I deserve more than lip service from the vehicle manufacturer. If they convince me via a process that is not "our policy is..." then I will happily do nothing.

The vehicle also has pre-paid maintenance. However, nothing in that schedule will address this concern.

FWIW, I have 20 years in the oil industry and have been a lubricant formulator for 15 of those.. I actually worked on the original 'black sludge' issues that afflicted Euro cars in Europe in the 80's and 90's.

With all due respect, changing a premium synthetic oil more often is not going to have a major impact on the mechanism for this particular potential mode of failure. However, I am happy to hear a reasonable technical argument that relates to the lubricant that may support this theory. Checking the separator and hoses often is a better option.

In essence, one of the bye products of combustion is water and how it is dealt with is the major issue...if the engine is allowed to warm throughly, the water is driven off or evaporates and will not collect or freeze at local cold spots. Short trips in cold climes do not drive off/evaporate the water. Whereas some oils (Group I base stocks) can be proven to be worse in the now, defunct Sequence IID test, invariably , premium fluids with genuine synthetic base stocks (not Group III) experienced zero problems and never exhibited any emulsion sludge in the breather hose.

Lubricants with poorer (read cheaper) base oils can be made to perform better in respect of emulsion sludge with very targeted and specific additives. However, the degradation with time will still make poorer oils worse in the long run than than genuine synthetic premium.

To be really technical, the polarity of the Group I base oils means they can solubilize more of the water generated during combustion wheras a true synthetic base oil (not Group III) is extremely non polar and will not solubilize the water so it tends not to get carried to areas of the engine such as the oil separator where it will do harm.

As you rightly state, driving habits are the biggest casual factor combined with a design oversight, weakness or fault depending on your perspective.

Outside that, the comment that regular maintenance is my best option is a little vague... if you have some very specific not lubricant related suggestions, I am happy to hear them.

On a personal note, it would be interesting to hear what oils folks were using on those vehicles that have experienced catastrophic failures .. I will do my research on what my stealer is using in my vehicle and if I am concerned, I may change the oil out now for something I know to be better.

One final note, the algorithm that BMW use in determining oil change interval uses, along with other factors, includes the number of key on, key off cycles so a consumer that does a lot of short trips where the vehicle gets started and stopped a lot and sits idle SHOULD have the oil change interval light illuminate sooner.

David

[JCL]

Originally Posted by nrgetic99

With all due respect, changing a premium synthetic oil more often is not going to have a major impact on the mechanism for this particular potential mode of failure. However, I am happy to hear a reasonable technical argument that relates to the lubricant that may support this theory. Checking the separator and hoses often is a better option.

I agree with the above. We don't know that the engines that failed all had premium synthetic oil. I would use a good synthetic, and if I was getting signs of emulsion sludge I would change the oil more frequently to flush it. Without getting into the lubricity questions (my tribology courses were 27 years ago) I would just focus on the visible signs of condensation. I go back to my point that this starts with short trips that don't boil off the condensation. The engine simply needs to get good and hot every now and then. We get posts such as "I only drove to the store" and "I left it idling for 30 minutes with no load in the cold and it got a hydraulic lock" and I think that those driving habits are the biggest contributor.

In essence, one of the bye products of combustion is water and how it is dealt with is the major issue...if the engine is allowed to warm throughly, the water is driven off or evaporates and will not collect or freeze at local cold spots. Short trips in cold climes do not drive off/evaporate the water.

Bingo. We have raging agreement!

As you rightly state, driving habits are the biggest casual factor combined with a design oversight, weakness or fault depending on your perspective.

I think that is fair, there are multiple perspectives. I do think that it would be better for BMW, and BMW owners, if the original design didn't allow this to ever happen. Having said that, proper maintenance (including the use of quality synthetic oils), not idling for extended periods in cold weather, getting the engine properly warmed up, all greatly reduce the odds. If a vehicle is 4 or 5 years old, cleaning out the crankcase vent lines seems like a very reasonable preventative maintenance step. I think BMW should put that in their Inspection II, rather than moving to heated vent lines. Most owners never have this problem. Some do, and it is unfortunate, but let's keep it in perspective. It is much more likely to not happen than to happen.

We could debate the performance of Group III oils, but I suspect we wouldn't get anywhere, too much of it is anecdotal. Besides, you would leave me in the dust. Your 20 years is in oil formulation; my 25 years since mechanical engineering school focuses on engines and service issues more than specific lubrication questions. I don't think this is a lubrication problem.

One final note, the algorithm that BMW use in determining oil change interval uses, along with other factors, includes the number of key on, key off cycles so a consumer that does a lot of short trips where the vehicle gets started and stopped a lot and sits idle SHOULD have the oil change interval light illuminate sooner.

I haven't seen that effect. I believe that the algorithm simply counts the litres of fuel consumed, and doesn't consider short trips vs highway. The different km/miles to an oil change is because of the relative fuel efficiency in those two extremes of highway vs city, not because the engine knows how it is being driven. You can see the measure of litres to the next oil change on the hidden menus in the OBC. There is no count of starts/stops to my knowledge.

Good discussion, as engineers are wont to have. One last question: Do you have any indication that the original stumbling was caused by this problem?

Jeff

[primetime]

nrgetic..Very well put..Alot of valuable info you gave us about the group number's for the different types of oil..I've heard that 0w - 30 is better for the winter's and then going back to normal 5w- 30 for the other seasons. Is this true? Or does it even matter?

[nrgetic99]

All :

Just to be clear here...I really appreicate the input and I am genuine in saying I welcome everyones suggestions...as you can probably tell, I am an engineer so by definition, I can NEVER have too much data

Many thanks..lets keep talking about this,

David

[X5 Meister]

Re: #1. There are different part numbers for all the different cars involved and remember there are different fixes as well (some involve replacing just one hose, some more then one hose, some wrapping hoses, etc.). What is your model and production date and I'll try to find out for you. Also what is the p/n of the separator that you got last year?

Re: #2. Thanks for the tips. BTW anything special I need to know to clean an MAF?

Re: #3. Very cool idea. Can't wait to see it!

[X5 in AK]

#1: Don't worry about getting the part numbers, I'm not going to by those BMW hoses. The p/n of the hoses I put on on mine (stock original) were 11-15-1-7-556-837 and -838.
oil sep p/n is 11-15-1-705-237 You also need a piece (about 3-4") of 1/2" PVC hose to connect the bottom of the sep to the drain line. Or buy a $5 piece of straight hose from BMW, p/n 11-15-1-438-302, which is made of the same crappy unreinforced rubber as the other hoses.

#2: Best way to clean a MAF is to remove the MAF insert from the housing, you will need a tamper-proof Torx bit (T-25, I think) to remove it. Then just follow the directions on the can and spray off the sensor/wire area. Reason for removing it from the housing is just to get better access. The screen guards on the housing limit access.

#3: Thanks, I'll be sure to work on it this summer.
Along with M5 maint/upgrades, boat maint, bathroom in the basement, building new snowmachine trailer.... I need to hire a garage boy to do all my projects for me.

[taosx5]

Originally Posted by X5 Meister

Re: #1. There are different part numbers for all the different cars involved and remember there are different fixes as well (some involve replacing just one hose, some more then one hose, some wrapping hoses, etc.). What is your model and production date and I'll try to find out for you. Also what is the p/n of the separator that you got last year?

Re: #2. Thanks for the tips. BTW anything special I need to know to clean an MAF?

Re: #3. Very cool idea. Can't wait to see it!

X5 Meister, I read X5 in AK post about changing the separator and am looking at doing this very wise PM. If I send you model and production dates, can you help me locate the hose (hoses) as mentioned above? This too sounds like a very wise move. I appreciate any words of wisdom you can pass on. What was done differently on X5s before and after Sep/Oct 03?

I also have a Dinan mass air flow on my 4.6. My son was visiting today and mentioned that it should be cleaned. I looked at it today when I cleaned the air filter and what on earth would you clean and how? Any thoughts anyone? Thanks in advance.