DIY Solution to M54-M52TU CCV problems

[cn90]

I just ordered the BMW OEM CCV parts for a CCV overhaul at 115K, simply because the original system is still fine at 115K, so I will stick to the stock setup for now.

However, in the future, if I have to do this CCV again, I may switch to this mod.

For comparison purpose:
- My 1998 528i (M52 CCV setup) consumes nothing between oil changes.
- My 2006 X5 3.0i (M54 CCV setup) drinks about 1 qt every 1,000 miles.

Since the CCV setup is very similar between M52 and M54, I think the oil consumption issue in M54 has more to do with the pistons rings etc. rather than the CCV thingy.


One another note, bimmerforums E39 M54 forum has something similar to the mod in this thread. See the DIY by mcgnms below:

M54 Oil Consumption Solved

[JCL]

Originally Posted by cn90

Since the CCV setup is very similar between M52 and M54, I think the oil consumption issue in M54 has more to do with the pistons rings etc. rather than the CCV thingy.

At one time we had three BMW vehicles with the M54 engine. All were driven by the same drivers, on the same roads, in the same ambient temperatures. All were purchased new and broken in the same way. All used the same oil. The E53 consistently used more oil, over several years of concurrent comparison. The only difference was that it was a heavier vehicle. The engine was working harder. (Which incidentally meant that it warmed up faster). In terms of oil consumption, I don't think CCV design had anything to do with it.

[Ricky Bobby]

^On the original CCV there is definitely a time element to this so cn90 its probably good idea to replace with updated cold weather parts since you are almost at 10 years old on stock system.

Just to get some peppiness back from the engine, less consumption, and increased mpg's sounds great on this mod. I wonder if doing this PCV and pluming a MannHummel ProVent100 in line would be perhaps the "ultimate" solution to the stock CCV?

[Ricky Bobby]

^^I'm talking about BavarianE39's CCV delete and "PCV inline" solution. He reports less consumption and increased mpg. Not talking about the factory CCV system.

[Ricky Bobby]

^There are many reports of people who have bypassed the stock system on the M54 (Bimmerforums, E46Fanatics, Bimmerfest) if you read some threads which report increased mpg, and literally zero oil consumption, compared to a working stock system. There are still some who have replaced with updated Cold Weather CCV parts and report oil consumption. I will check mine out when I get home tonight, but I just changed my oil in December and have put about 3k miles on it.

This is the first vehicle I've owned where consumption of oil in between changes is deemed "acceptable" even on a fully working and operational stock system.

BMW put the CCV system on for emissions as far as I can tell and environmental factors, that is more important in my opinion and most likely in their eyes, than fuel efficiency.


Bavarian can you remark about your fuel and oil consumption since installing the "simple PCV" solution, and as well, if you have any perceptions of increased peppiness from the engine as I have seen elsewhere.

[axgordon]

I would like to share my experience with PCV mod (Long...):
The car – 2003 3.0 - Purchased February 2010 at 115000 miles from the original owner. Strictly dealer serviced from day 1 (all documented). From the supplied service records, previous owner complained about oil consumption after ~ 70k miles. Per dealer evaluation, consumption within factory specs. Previous owner disclosed to me, that he adds at least 2Qt between 10k miles oil changes.
Having extensive experience with m52 and m54 engines, I did not want to take chances with CCV and within the first two weeks of the ownership, I replaced valve cover gasket, OFH gasket and entire CCV system except dipstick tube with genuine BMW parts. The dipstick tube was removed and properly cleaned from all gunks. I cleaned a fair amount of mayo from the inside of the valve cover and all CCV lines and valve itself was badly clogged with yellow stuff.
Prior and after the service car run perfectly fine – no smoke or any drivability issues. The car is driven daily and I avoid short trips. Car always parked in the garage where temperature never drops below freezing. The oil consumption slightly increased over the past five years to ~ 1.5Qt per 2000 miles.
Over the past two years, car develop small oil leak from the rear mail seal – no drops on the floor, however heavy oil deposit on the stiffening plate and the bottom of transmission bell housing. (Planned to replace rear main seal and torque convertor seal this spring. Even purchased new genuine seals and two stage transmission jack.)
I used Slack-Tube Manometer to measure crankcase vacuum - it was normal 6” – 8”, so I did not suspect issue with inadequate crankcase ventilation. Also, no visible mayo under the oil cap.
This spring I was prepared to replace CCV components again as a preventative maintenance, but before ordering new parts, I decided to try (proof of concept) PCV mod. I followed “BavarianE39” instructions with few minor changes – utilized ends of old CCV lines to make installation completely “Plug and Play”. Also positioned PCV valve vertically. Changed oil (BMW 5W-30) and filter same day at 188900 miles on the odometer.
First impression – Noticeably better throttle response from the stop – I did not anticipate this and it was very welcome change.
This past Sunday marked 2200 miles since installation (191100 on the odometer). The oil level remained at the upper mark on the stick!!!
The stiffening plate and the transmission is bone dry!!!
I did not notice change in MPG
Conclusion – considering age and the mileage of my car I am not planning going back to stock CCV. And no more fear of hydro locking engine during winter!
If anyone interested to experiment with it – let me know and I will post pictures of my setup.

P.S. Cracked open old CCV – after 75k miles nothing clogged, reasonable amount of carbon buildup and rubber diaphragm appears to be in good shape. Checked dipstick return tube - it is not clogged. Go figure if anything is wrong with the stock system.
My son’s 2001-530i hydro locked engine in February 2013 with two-month-old CCV system. That car consistently consumed 1Qt per 900 miles before and after CCV replacement. Parked outside and driven to / from school 5 miles each way.

In response to the” Trader4” point about valve cover design – please compare attached images of valve covers from m30 (old BMW engine with basic crankcase vent system) and m54. Please note that I never took internal plates from any of these covers, so cannot elaborate on what is behind, but as you can see, both valve covers have some internal plates covering ventilation hole.

[axgordon]

Originally Posted by trader4

Trader4 – All good points. I am myself firm believer in the effectiveness of stock components and always try to use genuine parts for critical systems. This situation is little different. Let me try to answer some of your questions:

If you think having to add oil between oil changes is unusual with high mileage, 10+ year old cars, then you must have some exceptional
vehicles.
Ricky’s car is not high mileage car - less than 80k miles if I remember correctly. My 528i with m52tu engine did not consume a drop of oil at 180k miles

Of course BMW put the CCV system on for emissions. My point was
that if it results in a decrease in MPG compared to the simple PCV
type design, then they would have to be pretty dumb to use the oil
separator design when they are desperate to increase MPG.
All the other manufacturers of all kinds of vehicles are meeting EPA with PCV type designs.

Yes. Original BMW CCV system works perfectly fine on m52tu motors. I did not found any reference that m52tu ever hydro locked in cold climate. The only known mode of failure – slugged CCV causing oil leaks and drivability / idling issues. The only substantial difference in design between m52tu and m54tu is low-tension rings on the latter. I spoke with the reputable performance shop owner and he confirmed that he successfully fixed high oil consumption on two m54tu by replacing piston rings. My theory here that extra blow by gases reach in H2O on m54tu causing simply overload capacity of stock CCV system. Apparently, these low-tension rings starting to fail at 60k+ miles causing excessive blow by. This is why we do not see mayo on low mileage m54tu. It is frozen mayo causing catastrophic failure of CCV and hydro lock as of result.

Perception of peppiness is almost meaningless, given the high potential
for the placebo effect.

Cannot argue here. Nevertheless, I noticed better performance myself.

BTW, you didn't answer the question as to what the reference point
for these claimed benefits is? A new, stock CCV system? Or an old 100K,
stock one that is possibly failed, known failed, etc.

I was trying to provide this information in my original post. I used my car stats with old, new and aged CCV system. I thing that 5+ years routine of adding oil every 2k miles is reasonable reference point.

[cn90]

Originally Posted by trader4

If you think having to add oil between oil changes is unusual with high mileage, 10+ year old cars, then you must have some exceptional vehicles...

My E39 1998 528i with 150K miles with M52 engines drinks no oil between 6K oil change interval. Nothing, zip, nada oil consumption.
Nothing!

M54 is another story...

[Ricky Bobby]

^axgordon, please share pics of your setup and parts needed to make it look cleaner and completely "plug and play"!

How was vaccuum since converting to the simple PCV system?

[axgordon]

Originally Posted by Ricky Bobby

^axgordon, please share pics of your setup and parts needed to make it look cleaner and completely "plug and play"!

How was vaccuum since converting to the simple PCV system?

Ricky,
See attached pictures. I did not measure vacuum after the mod yet. The crankcase remains under vacuum for some time after the engine shut off - i don't see any issues with that.