DIY Solution to M54-M52TU CCV problems

[80stech]

Very good theory! That does make some sense. I think also though there is another factor involved that has been addressed by some of the guys doing the mod. I think the BMW engineers got a little bit sloppy on the design of the valve cover baffle and in the way the vent tube comes off the valve cover thinking that the oil seperator would take care of any oil that got sucked in to the CCVC. By doing the mod (depending on how you go about it) there is less chance of the little bit of oil that collects on the bottom of the valve cover tube to getting sucked out.

[80stech]

As far as the freezing/moisture problem I think of it this way, The crankcase is closed so it is filled with moisture saturated combustion gases. The moisture ends up forming dropplets, which get seperated in the cyclone oil seperator, which ironically works much better seperating heavey moisture droplets than it does oil, and returned to the crankcase. The CCCV can only get rid of moisture vapour not droplets, so the only way to reduce the moisture is to let in a little unsaturated atmosphere to absorb it and let it get sucked through the seperater and into the intake as vapour.

[Scott ZHP]

Originally Posted by cn90

the oil ring (the bottom ring) is low-tension and has a gap of 2.5mm after some 120K miles. This gap allows oil to sneak up and sucked into the chamber during intake stroke.

When the M54 is new, the gap is small (? 0.4mm), so virtually no oil sucked into chamber.
As mileage adds up, this low-tension ring wears out, creating the gap of 2.5 mm.

I think you are on the right track. I'd offer that the lower oil control ring gets sludged up and sticks to the ring land. In order to be effective, the ring needs to spin. Some of the piston pics on E46Fanatics are disturbing.

[cn90]

My 2006 X5 M54 engine used to drink 1qt/400-500 miles.

Did the LOWER engine treatment (don't have time to do UPPER treatment with AC Delco thingy). This is what I did:
- 3/4 qt ATF in engine oil for 200-300 miles.
- At oil change, used Lubro Moly Engine Flush, ran engine for 10 min, then replaced oil + oil filter.
- Oil consumption is still the same, i.e., 1qt/400-500 miles

Then I did the poolman, Bavarian CCV mod, 500 miles later zero oil consumption!!!


I am very convinced that my theory above (more crank case vacuum ---> much less oil gets sucked into combustion chamber) is correct.

The key thing is the PCV Valve reducing the flow to appropriate level (3/4-inch ---> 3/8-inch). Some people on youtube didn't use the PCV Valve but they used plumbing adapter to bring it down to 3/8" or so. I still recommend the PCV Valve. Just replace/clean it every 10K-15K or whatever interval you are comfortable with.


This is my setup, thank you all for contributing.



---

[cn90]

UPDATE: Zero oil consumption after 500 miles with CCV Mod.

2006 X5 3.0i M54 engine 6sp MT with 122K miles.

1. Did the LOWER end treatment:
- 3/4 qt ATF for 200 miles.
- Ten (10) minutes before oil change, one bottle of Lubro Moly (500 mL) into engine oil. Ran engine at idle for 10 minutes.
- Changed engine oil and oil filter.

---> No change in oil consumption: still 1qt/400-500 miles!


2. Did the CCV Mod (Duralast 1124 Valve as in the photos).
- After 500 miles, zero oil consumption, unbelievable.
So this CCV Mod rocks!!!

Thank you all for saving my motor!!!

[Sroor9001]

Originally Posted by cn90

UPDATE: Zero oil consumption after 500 miles with CCV Mod.

2006 X5 3.0i M54 engine 6sp MT with 122K miles.

1. Did the LOWER end treatment:
- 3/4 qt ATF for 200 miles.
- Ten (10) minutes before oil change, one bottle of Lubro Moly (500 mL) into engine oil. Ran engine at idle for 10 minutes.
- Changed engine oil and oil filter.

---> No change in oil consumption: still 1qt/400-500 miles!


2. Did the CCV Mod (Duralast 1124 Valve as in the photos).
- After 500 miles, zero oil consumption, unbelievable.
So this CCV Mod rocks!!!

Thank you all for saving my motor!!!

I think there is pilot modification only hose from vent in ccv to the back of the manifold and you got same effect of vacum
I think it's done by 50s kid on e46 on YouTube

[bcredliner]

IMO there is no connection to eliminating the oil consumption and that it is good, or bad, for the engine. Would anyone do this on a new car?

[Joshdub]

Originally Posted by bcredliner

IMO there is no connection to eliminating the oil consumption and that it is good, or bad, for the engine. Would anyone do this on a new car?

This has been discussed to great length on other forums. According to them, the M54 has low tension oil rings. Increasing crank case vacuum helps these rings seal, stopping oil consumption. Oil consumption seems to be hit or miss on M54s, but this has been a documented issue since they were first released. I'd wager that is why there is the extra capped vacuum port on the CCV and the corresponding capped port on the intake manifold. Funny enough, running a vacuum line from the CCV to the intake manifold (as shown in realoem) significantly helps, if not cures, the oil consumption issue.

[Ricky Bobby]

^Josh did you do it on yours? Which one of the ports did you run it to? I really dont want to do the CCV job again since I only did it 2.5 years ago but this may be a good way to do it since I already upgraded to cold weather parts.

I replaced those small vac lines at the back of the manifold and the vac caps earlier this year.

[bcredliner]

It has been documented that this mod can stop oil consumption. Has it been documented if the practice is good or bad for the engine? Anybody checked if there are downsides elsewhere? Anybody know if this has been driven by saving money verses cost of rebuilding BMW system? Or, by someone that is a CCV 'expert'? What I read is it is a theory, according to, odds are, etc.

Not taking a position either way just pointing out there may be potholes on this road worth consideration.