Intake Valve Carbon Blasting

[fe1rx]

My 2008 N54 has 100,000 km (60,000 mi) and is put away for the winter so I decided to carbon blast the intake valves. I purchased the vacuum adapter from ECS Tuning and although I have a large pressure pot style sandblaster, I bought a portable unit for this task because configuring it looked much simpler. For blasting media I bought a 50 lb bag of 20/30 grit walnut shells.

I used the excellent Bavarian Autosport DIY video for getting the head exposed:

The blaster I used is a Zender "Speed Blaster". I got mine from KBC Tools, but they are widely available and about $60. I ended up making a few different wand attachments from a length of 5/16" steel fuel line tubing. I modified a brass hose barb fitting to replace the ceramic nozzle and used some 5/16" silicone tubing to tie things together. Initially I tried 1/4" tubing but this proved too restrictive and did not work well.



The vacuum adapter is an excellent tool as you would expect from BMW. It fit the small extension hose I have for my shopvac with no adapters being required.

http://www.ecstuning.com/BMW-E82-135...ols/ES2165972/

All told I used about 25 lbs of media to do the job, so a decent-sized shopvac helps. With practice, I could probably get a bit more efficient with my media consumption. I did get a bit better as I went along.



I would characterize my intakes as definitely due for cleaning. It is difficult to see the deposits unless you shine a very concentrated light directly in the port because the carbon is remarkably black. This makes photographing the deposits a bit tricky. Each port was slightly different in terms of buildup, with 6 being worst. The thickest deposits were about 1/8" thick and are very gummy. I was expecting a harder coating.





I found the best technique to be a combination of blasting, scraping and scrubbing. An initial scraping of the thick deposits really seemed to speed up the blasting. No need to scrape them out, just scrape them off and let the blasting evacuate them.

Step 1 scraped:



Step 2 initial blasting. Getting to this point took only about a minute of blasting after the initial scraping - much longer without the scraping:



Step 3 done. If you want a perfect job (and of course you do), it takes quite a bit of work to get every area of the port cleaned. A pressure pot style blaster with a 1/4" wand might have made access a bit easier:



A small stainless steel wire brush is helpful to clean the mouth of the port that is obstructed by the vacuum adapter. Some carb cleaner or equivalent and rags complete the job. It took me almost an hour per port on average to clean the ports using this approach. A pressure pot and some practice could probably cut this time in half.

Clearly this service needs to be scheduled and not based on symptoms. 100,000 km is too long an interval. It probably makes sense to synchronize this service with spark plug replacement. Both tasks are fairly labour intensive but not particularly difficult so doing them yourself makes sense if you have access to an appropriate shop. Certainly the investment in tools is easily paid off if you use an economical blaster. A more frequent service interval should also make the cleaning easier.

[Bullitt]

Thanks for the post. I replaced my plugs recently and saw deposits in the chambers below them. Was surprised to see the amount of carbon as my engine has less than 40K miles with an oil catch can always in place since delivery, on stock boost mostly. Doing this at the same interval as plugs seems sound.

Shops here charge an amount that would cover the investment for the tools required for this job, if not more. Once unsure about the DIY, not anymore

[scott_b]

Good post. I blasted mine this past fall using the BAV video as well. It's really not a bad job to do yourself if you already have a compressor. My car had around 55k miles at the time of blasting. After blasting, I purchased a BMS Oil Catch can. We'll see if that makes a difference next time I go to blast.

[scott_b]

On a side note, if you do plan to do this, I would purchase the aluminum vacuum adapter like the OP has in his picture rather than the composite one that BAV sells. The composite one is not very strong and will break easily. Trust me.

[dubluv17]

Could you post what the total cost of parts was for you, please?

[fe1rx]

Originally Posted by dubluv17

Could you post what the total cost of parts was for you, please?

The parts needed are:

Intake gaskets (set of 6) p/n 11617547242
http://www.ecstuning.com/BMW-E82-135...h/11617547242/

Throttle body gasket (1) p/n 13547522361
http://www.ecstuning.com/BMW-E82-135...h/13547522361/

Assuming you have a compressor, the tools you need are:

BMW Cylinder Head Adapter
http://www.ecstuning.com/BMW-E82-135...ols/ES2165972/

Portable sandblaster - I used this one:
http://www.zendextool.com/speedblaster/
McMaster Carr p/n 31195K11

about 25 lbs of 20/30 Walnut Media
http://www.mcmaster.com/#blasting-media/=w5exdy

[fe1rx]

The engine is now up and running, but threw a P30FF boost leak code. Viewing live boost data with the Cobb showed I was getting no boost at all. That indicated that the turbos were not building boost or I had a massive air leak. Hearing no air leaking noises, I suspected the former. Pulling things apart I found one of the lines taking vacuum over to the wastegate control solenoids was broken. These are easily jarred when pulling off or putting on the intake manifold. Probably best to move them out of the way next time.



That is item 5 below:

[drewster99]

I'm about to buy the whole kit from BAV. I only have a tiny 2 gallon air compressor, will that be enough or should I find someone's 20 gallon to borrow?

Also, would spraying seafoam into the ports before blasting them help break it up a little?

[fe1rx]

Originally Posted by drewster99

I'm about to buy the whole kit from BAV. I only have a tiny 2 gallon air compressor, will that be enough or should I find someone's 20 gallon to borrow?

Also, would spraying seafoam into the ports before blasting them help break it up a little?

That sounds like a small compressor and will likely slow your progress. A lot of blasting is required, so a lot of air.

Seafoam will make a mess and not help. It is potentially useful for final cleaning of small areas, but as for helping with the bulk of the carbon, definitely not a good idea.

[fe1rx]

Here is another view of the pinch point. Getting the intake manifold on and off does take some wrestling, so moving the two vacuum hoses aside is probably a good idea for both operations.

[135TX]

awesome work!! Sorry about the vacuum line

[drewster99]

Originally Posted by fe1rx

That sounds like a small compressor and will likely slow your progress. A lot of blasting is required, so a lot of air.

Seafoam will make a mess and not help. It is potentially useful for final cleaning of small areas, but as for helping with the bulk of the carbon, definitely not a good idea.

Okay, thanks. I'll find another compressor!

[Sasha4]

Did you have an erratic idle just at start? Ive been told this is the cause but otherwise my 135i runs strong. Ive replaced the plugs and ignition coils (recommended by Turner Motorsports) but no change was felt or heard.

[omgshinoda]

if you replaced both plugs and coils, the next in-line is the injectors