[Novo777]

Hello everyone! New here, just joined and just got new to me 2010 335d I am deployed right now but will be home in less then 2 months. While here, during free time I have been reading up on this issue with CBU. My 335d has 66k miles on it and I am guessing I will be cleaning it when I get home! The question I had is about the ports! I am guessing there are lower and upper ports? Are the square ones the high speed ones and the round are low speed ones? Does the walnut blaster scar the valve cover since it's made of plastic or you don't pull out the wand far enough so not to hit the plastic part with shells?
Glad to be part of this great forum! So much useful information and so many knowledgable and kind fellow BMW enthusiasts that are working together as team to solve problems and improve our rides!

[command_liner]

Originally Posted by Novo777

Hello everyone! New here, just joined and just got new to me 2010 335d I am deployed right now but will be home in less then 2 months. While here, during free time I have been reading up on this issue with CBU. My 335d has 66k miles on it and I am guessing I will be cleaning it when I get home! The question I had is about the ports! I am guessing there are lower and upper ports? Are the square ones the high speed ones and the round are low speed ones? Does the walnut blaster scar the valve cover since it's made of plastic or you don't pull out the wand far enough so not to hit the plastic part with shells?
Glad to be part of this great forum! So much useful information and so many knowledgable and kind fellow BMW enthusiasts that are working together as team to solve problems and improve our rides!

There are 2 sets of ports in the head, round ones on a long tube and short ones with square ports. The single manifold works with both. The "swirl port" system switches between the low-speed mode dominated by the long tubes and the high-speed mode dominate by the square ports.

Tis all so very much like the early 1990s ZR1 corvette motor which used two separate intake manifolds and 2 throttle bodies to do the same thing. Also reminiscent of the Chrysler wedge cast iron long tube cross rams from the 1967 era.

Back to the present day... The ports get coated with carbon matrix from partially combusted CCV which has been run through the EGR. Consistency varies from chewing gum to urethane bed liner.

You do need to be careful not to scar the intake with the walnut blaster! I made one small mark. OTOH, you do have to scrape the inside of the valve cover quite a bit. Carefully!

The round ports are the "swirl ports" and are not easy to clean. Working with an assistant, it was 20-30 minutes a port for me. The square ports are the "tangential swirl ports" and may be easier to clean -- I do not know yet.

[Novo777]

So to understand this easier - I need to use walnut plaster deep inside and use some kind of scraper on the valve cover portion? Is there any way to find out if this has been done to my car yet by calling BMW dealership or the only way to tell is to take off intake manifold?

[kbsilver]

Originally Posted by Novo777

So to understand this easier - I need to use walnut plaster deep inside and use some kind of scraper on the valve cover portion? Is there any way to find out if this has been done to my car yet by calling BMW dealership or the only way to tell is to take off intake manifold?

Intake most definitely must come off to clean it. The tools/wands to clean the engine are very specific to this particular engine and are not used on any other type of engine. The walnut blasting/vacuum attachment gets most of the gunk, but some manual scraping with a long pick in combination with a boroscope may be necessary.

Remember the engine crank is turned to ensure the valves are fully closed on the cylinder being worked on (believe this is why the valve cover comes off). This really is not a DIY. Experience is probably the most valuable part of the entire procedure.

If the car ever had CBU cleaning at a dealer, there is a record.

[rulonger]

Originally Posted by Novo777

Is there any way to find out if this has been done to my car yet by calling BMW dealership or the only way to tell is to take off intake manifold?

I asked the SA to review all service history of my car and he obliged. On the service records of interest to me (ones that sounded more involved), he actually pulled of the detail technical notes and read them to me from the screen. He said that he could not print those for me, but he let me take notes. It was in this review of the service record that I discovered that my CBU cleaning occurred at 31,600 miles. I had purchased my car as a CPO at 41 K miles.

[command_liner]

Originally Posted by kbsilver

Intake most definitely must come off to clean it. The tools/wands to clean the engine are very specific to this particular engine and are not used on any other type of engine. The walnut blasting/vacuum attachment gets most of the gunk, but some manual scraping with a long pick in combination with a boroscope may be necessary.

Remember the engine crank is turned to ensure the valves are fully closed on the cylinder being worked on (believe this is why the valve cover comes off). This really is not a DIY. Experience is probably the most valuable part of the entire procedure.

If the car ever had CBU cleaning at a dealer, there is a record.

Sure, the intake must come off for the cleaning.
The wands are bent up pieces of steel brake line. They are hardly special, except in the way the drain your wallet. OK, the BMW units are stainless steel brake line with a nice finish on the end.

The vacuum adapters are ... a waste of money. Yes, they are nice sand cast aluminum machined well. They come with plastic fittings you need to throw away and replace with a $9 fitting from HomeDepot. Save your money.
Instead buy a pair of vacuum fittings from HomeDepot, a sheet of 1/8" Lexan and some 0.030 welding wire. Cut the lexan to make suitable port covers and stitch these onto modified vacuum fittings from Home depot. Drill holes in the HomeDepot fittings to run the brake lines.

You absolutely need the borescope to figure out when the ports are actually clean. Without checking, you are just guessing.

The blasting wands work pretty well for the head, but will eat through the valve cover and intake, so you cannot use them on the tops. This requires manual scraping and (in my experience) a terry-cloth-acetone scrub.

[Novo777]

Excelent comane_liner! Thank you! I have some experience with engine work! I used to have 740iL and 540i, I did head gasket job on boxer 2.5L and bunch of other small jobs here and there! Making my own tools is common in my garage!!! Do I call any BMW dealer and ask the servise department if they could look up my car by the vin? I will take my time and surely and slowly will clean it out once I get home! After that I was planning to get JBD and Meth and should be set for 30k miles! Hopefully!

[command_liner]

Almost done with the cleaning. If only the day job did not take so much time. Only the #6 easy/square/high-speed/tangental-swirl-port is left to do.

I did these last 5 ports without the port vacuum adapters. It was messy, but faster and better than using them. I am on my second use of the 25 lbs of walnut shells. If time permits, I will do a full write-up on how to do this work without all the cost of the dealer or the BavAuto kit.

[AustinMsport]

Originally Posted by command_liner

Almost done with the cleaning. If only the day job did not take so much time. Only the #6 easy/square/high-speed/tangental-swirl-port is left to do.

I did these last 5 ports without the port vacuum adapters. It was messy, but faster and better than using them. I am on my second use of the 25 lbs of walnut shells. If time permits, I will do a full write-up on how to do this work without all the cost of the dealer or the BavAuto kit.

That would be awesome!

[command_liner]

We finished blasting the ports tonight. I got one really good photo of a clean port, showing the valve and a bit of walnut. There are no "before" photos because it was full of black goo, just like the photos of the intake.

The intake is sitting upside down on the fender because I dropped one of the hold-down nuts and cannot find it! It went someplace on the left side of the engine and may as well be on Mars. After 70 minutes I stopped looking for it. Tomorrow I will go and buy a similar nut.

You can see a pair of good shots on the photostream of the belly pan where oil leaks from the boost hose. The dealer claims not to have spotted any oil leaking there! Sure! Now that the warranty is done, there is clearly oil leaking.

How do the gaskets for the high-speed ports stay in place when you flip the manifold over? I am thinking about a thin film of RTV. Any other suggestions?

[Hoooper]

Originally Posted by command_liner

The intake is sitting upside down on the fender because I dropped one of the hold-down nuts and cannot find it! It went someplace on the left side of the engine and may as well be on Mars. After 70 minutes I stopped looking for it. Tomorrow I will go and buy a similar nut.

These engines will gladly hide anything you drop. I lost a 3" long 3/8 extension down near the hpfp a while back, spent a whole day just looking for it and never found it. Had the good open a week later and the extension was sitting neatly on top of the hpfp just aside from the pulley. Black magic...

Originally Posted by command_liner

How do the gaskets for the high-speed ports stay in place when you flip the manifold over? I am thinking about a thin film of RTV. Any other suggestions?

They just stay in there, never had any try and come out.

[Novo777]

Any updates on cleaning?

[command_liner]

Originally Posted by Novo777

Any updates on cleaning?

I have had a cold that has kicked my ass up and down the street. A few days off from work and nothing getting done. Weekend wasted too.

The top end is together, except I am waiting for the boost hose gasket set, which has been delayed for about 2 weeks through my local dealer. It should be here tomorrow and I can close up the boost circuit.

I dropped the front-most lower intake manifold nut, and it disappeared into that alternate universe where small parts go. It was not an easy thing to find a 7mm fine nyloc nut to replace the flange nut from BMW. The local tractor parts place had something suitable.

[sour335d]

I want to thank you for sharing your experience with the CBU cleaning, and for outlining the process with your observations and pictures. I'll probably perform the cleaning in the weeks to come. I'm sure your thread will be a very valuable resource.

Hope your car gets back up and running soon!

[Novo777]

Thank you command_liner.

[command_liner]

Today we got the car back together. I had made a small mistake re-installing the band clamp around the EGR feed and had to order a replacement clamp. BMW of Portland got one out via UPS and it came overnight. (That was good luck, but they 'accidentally' hit my Amex card for $177,971.00. I declined the charge, but had to spend time clearing that up.)

The car went back together minus the sound isolation pad and started after a bit of cranking. After letting it warm up, I took a *short* drive and it went into limp mode. Turbo underboost and excessive EGR flow. http://www.e90post.com/forums/images...es/mad0260.gif

Since I had the tooling and the right alloy, I made a new stainless steel EGR block off plate. No excess flow with that in place! After the codes were cleared the car went out for another drive. Limp mode again, but this time only with 0402, excess EGR flow.

Since there is an EGR blocker plate, there is zero EGR flow, so there can be no excessive flow. What next? Is there a flow sensor for the EGR that can be changed?

Working through the EGR issue, I noticed that pressure in the EGR system was substantial. What is the typical running pressure for the hot exhaust? The pressure must be substantial in order to overcome the boost of the compounded turbos, but what is the pressure?


I just added a photo of the new, installed blocker plate to the tail of the Flickr album.

[Novo777]

Do you have the time that codes out the EGR?

[command_liner]

Originally Posted by Novo777

Do you have the time that codes out the EGR?

Time?
After a bit of thinking, I assume you mean "tune". No, I have no tunes. Bone stock.

[335dFan]

Originally Posted by command_liner

BMW of Portland got one out via UPS and it came overnight.

Good to see another one nearby Portland OR?

[command_liner]

Originally Posted by 335dFan

Good to see another one nearby Portland OR?

Yes, an hour or two south. Out in the unincorporated sticks west of Albany.

I might throw a fresh MAF in and see what that gets me.

[Novo777]

Everywhere I read it says that if the EGR is blocked off you need a tune. Oh and clever you figured out my crappy spelling "time"! i did mean tune! Anyway, the EGR has to be blocked off on both sides, and tune that deletes the codes has to be ... Tuned I guess, that's the right way to say it. I believe Jarek in Canada and Lenny in Florida do those specific tunes. TDIwyse, iaknown and PR would know more, they have it all figured out and have no codes!

[Novo777]

Originally Posted by command_liner

Yes, an hour or two south. Out in the unincorporated sticks west of Albany.

I might throw a fresh MAF in and see what that gets me.

I doubt a new MAF will do anything for you brother, considering the code is narrow and points to EGR fault!