Dwight, nice fitment. Glad to hear 42DD works. They looked like they knew what they were doing. Some catch cans do not. ( catch can, not vapor separator) I still run stock intake, so a place to put it is yet to be found. The longer the lines the better actually. The DOS intake sure makes that an easy fit. Might be a slick addition to make a fitting to inject cleaner post separator.

 

You can make a catch system with a non filtered water seperator from a compressed air system. I have before ittl run you 50$ does not look goos and finding the fittings to match the mini might be a pain but it works. On my boosted s2k and wrx i made my own catch system. They work!


http://www.homedepot.com/Tools-Hardw...atalogId=10053

kind of like the one i used, i guess it was discontinued, but as long as theres no filter and just baffling itll work.


.02 food for thought

 

If buildup occurs before 50K that affects engine performance, it is an emissions control issue and Mini IS responsible under Federal law. They have proven to not stand up, so I am not surprised at their attitude. I guess they are right. I already will never buy another BMW product, so treating me well will not gain them any future business. I need a slightly larger car. Like the 135. Guess I'll by a TSX.

In the mean time, I think I'll order me a 44dd can.

 

OK TVRGEEK, but I'm gonna get my 2 dracmas in at the start, LoL. I first started digging for info on DFI engines about a year ago. A cousin belongs to SAE and told me about the carbon problems, but when he tried to describe it he lost me. Engineers don't speak any form of English I'm familiar with. Wish I could remember the R & T issue that DFI article was in, but here's how I remember it:

The DFI is the cause of the problem as there is no longer a fuel/air wash to clean the intake valve stem and head. The carbon build up is on the intake side of the valve not on the combustion chamber side. To me that eliminates the ring seating idea.

The carbon is coming from crankcase oil mist and and half burned crud dumped on the intake valves by the PCV system. The crankcase is pressurized by combustion blow-by of the rings. Turbo/supercharged engines create higher combustion pressures and even a normal engine will if driven hard. BTW, you can't have perfect ring seating and seal or the piston couldn't move.

Ford seems to be using some kind of trap that allows the PCV vapors to drain back into the crankcase. However, when I asked the local Ford people about it, they had no idea what I was talking about. They even said all Ford engines were DFI! I left.

To add more confusion, all engines will eventually develop this problem, it just happens faster on DFI engines. Ever check out the intake side of a small block V8 with 80K miles on it? Pretty grim.
OK, now someone else can chime in.

 

Since the consequences of carbon build-up are so dire (ruined engine, etcetera), would it be possible/practical to just disable the PCV system entirely?

I don't have a dog in this fight (1st-Gen MINI with no build-up problems), so I'm just asking out of curiosity. I'm usually not a fan of bypassing pollution-control systems, but with no satisfactory solution in sight for the carbon problem, it seems like it might be an option.

 

Scot,
The PVC is there for a good reason. EMISSIONS. We don't want that crap in the air. If you disable it, the car will throw a code as it expects vacuum in the case and of course, it is strictly illegal.

Dwight,
Thanks for the search. You did contradict yourself. It seems to be agreed that the source is the crankcase vent system, i.e from the PVC valve. We all agree that there is no gas additives to wash it clean. But the source of the vapors is blow-by, so the quality or effectiveness of the rings seating would be the prime source. This is why I was asking for comments on break-in and amount of problem. It is looking like the correct solution is to do what the OEM is loath to, Add a part that costs money. A vapor separator.

Yes, I thought about one off a air compressor. Too small and most have built in regulators. I think I am going for 42dd's unit unless I make one to my liking.

Sounds like other than why some are far worse that others, this is wrapped up.

 

[quote=tvrgeek;3122168]Scot,
The PVC is there for a good reason. EMISSIONS. We don't want that crap in the air. If you disable it, the car will throw a code as it expects vacuum in the case and of course, it is strictly illegal.

Dwight,
Thanks for the search. You did contradict yourself. It seems to be agreed that the source is the crankcase vent system, i.e from the PVC valve. We all agree that there is no gas additives to wash it clean. But the source of the vapors is blow-by, so the quality or effectiveness of the rings seating would be the prime source. This is why I was asking for comments on break-in and amount of problem. It is looking like the correct solution is to do what the OEM is loath to, Add a part that costs money. A vapor separator.


I guess I didn't state that very clear so I'll answer your comment about piston ring blow-by being the source of the problem with a question. If that really is the source, how does the carbon build up end up on the "outsde" of the intake valve and not on the combustion chamber side? Siminiatus's column in R & T clearly stated that the PCV was the source of the carbon build up.

 

Where is this column? I would love to read it.

 

It was in an issue earlier this year, but unfortunately I re-cycled it. I believe you can get reprints from them and I'll give it a try, but don't hold your breath.

 

I don't suppose you remember the cover? Or the author/title?

 

Sorry, but I don't remember the cover. Dennis Simanaitis was the author. He writes a monthly column for R&T called Tech Tidbits and is one of those rare birds that can translate engineerspeak into normal English. I think your best bet on finding it is to dig through the magazine morgue at your local library. When I get a chance, I'll do the same. Happy digging!

 

Step away from NAM for a while and look at all the fun I miss.

Of course break in affects the problem. But that's really not too important. there is blow by in all engines, you're really just talking the degree. And wear makes it worse....

Also there is engineering. Anyone notice that the Prince Turbo valve cover part number changed a while ago? I'm guessing that they tried to do better phase separation to reduce the amount of oil that they spewed into the PCV system.

And phase separators are not new. My 75 Fiat 124 had one, and the block on that was designed sometime in the stone age! Or the early 60s, I think.

And of course port injection helps reduce the problem. Look at injector duty cycles. The suckers are pretty much open for the whole cam rotation at redline and WOT. The spray puddles and is sucked in when the valve opens. the intake valve gets a good wash each and every intake cycle.

And it's not on the exhaust because all the crap is burned up in the combustion chamber.

Anyway, for the guy who only runs 3500 miles a year, you might want to do it anually just cause that's easy to remember. It's probably more often than you need, but WTF, easy to remember is good too.

The comments about geographic distribution are interesting, but what is one gonna do? Move to Denver so as to not have the problem? There is also questions about regional difference in gas chemistry. And the population density is true is well. CA has what, 8-9 dealerships? How many do the whole plains states have? Most of the cars ARE sold on the coasts. how to deconvolve all this is rather pointless. The problem is real for sure. And pretty widespread on gasoline DI engines. But we'll be seeing more of this, not less. More and more manufacturers are going DI and turbo for increased fleet efficiencies. Maybe they are taking it more seriously now.

Oh, while it's not MINI, Mazda is coming out with a new DI gas engine for 2012/2013 that will be widely deployed. 14:1 compression ratio! Zoom zoom indeed! Wonder what they'll be doing about blow by and phase separation.

Matt

 

Yikkkkes! That should be fun

 

For those (like me) who may be unfamiliar with what a PCV system is and how it works, this series of short videos might be quite informative…

PCV System - Moss Motors

 

Question? What effect would running a tank of 100 Octane non-ethanol race fuel have on carbon deposits? I'm "told" it will clean up carbon deposits .... but would like more opinions.

 

100 octane gas will do absolutely nothing for carbon deposits on a DFI engine.

 

I think that people are still missing the whole "DFI" point. This is the root cause of the problem as explained earlier. It's not the same style as almost all typical gas/air apps of the past. The intake valves are isolated on one side in the directly injected configuration.

Does anybody have a cross-sectional cutaway of the N14 combustion chamber and cylinder head?

 

Thanks, "fish". Filled my learning quota for today!

 

Matt, that would be me

I'm probably going to wait until my next oil change in April 2011, at which time I'll be at around 6500 miles. I'll have to dig up the Seafoam R56 Youtube video(s). I remember somebody had a question about which hose to actually run the Seafoam into. I don't want to do anything screwy.

Thanks for the suggestion.

Ric

 

lol looking at the engine from the front, thick hose on the upper left of the valve cover..., simple as that

 

Quote:
I guess I didn't state that very clear so I'll answer your comment about piston ring blow-by being the source of the problem with a question. If that really is the source, how does the carbon build up end up on the "outsde" of the intake valve and not on the combustion chamber side? Siminiatus's column in R & T clearly stated that the PCV was the source of the carbon build up.[/QUOTE]

Possible confusion on the term: Blow by is from the combustion chamber past the rings into the crankcase, and hence, out the PVC to the manifold where it encounters the nice hot backside of the valve.

 

Yes, we are way past that. Everyone agrees that a DFI does not have the fuel additives spraying on the back of the valve. The only question is why there is such a large variance in how bad it is car to car. My hypothesis is the method of ring seating in break-in. Others have suggested it is related to one's right foot. The real answer may be "yes".

I still wonder what is done on diesel engines? Do they all have vapor separators?

 

Variance in average rpm (frequency of combustions, and thus frequency of blow-by),
variance in gas quality (how much "stuff" is left over to blow-by the piston),
variance in the tolerance of cylinder diameter and piston diameter (amount of gas allowed to blow-by per combustion),
variance in user observations of the effects (I haven't seen many physical measurements of carbon build-up rate in here),
etc.

There could be quite a wide range in the severity of reports, I would think.

 

I wonder if not changing the oil after break in (1500 mi. 3000 mi.) has an effect on this. Some NAM members have posted how much stuff is in the oil at 15,000 miles from their lab results.

 

I would think that short trips around town and not getting the car up to full temperature for a period would also be a consideration. I am thinking that somebody who has a good long commute probably would see this less than somebody who goes 3-5 miles up the road to work every day? I certainly think that gas quality, temperature and ability to full heat cycle all play a part.