Walnut blasting is crap. It has to be manually removed. Walnuts are only good for eating and baking.

 

I think it is obvious that you have no experience with walnut blasting. I've used it to remove paint from sheet metal, it takes paint off fast and doesn't affect the metal underneath.

Dave

 

+1...it does wonders

 

Walnut blasting is GREAT on thin metal or soft metal to ensure no damage. Cleaning carbon deposits off the intake manifold of an engine is a whole other ball game. It's definitely NOT 100% good to go which = crap as far as I'm concerned.

 

tominizer, I would like ask you to be a little more descriptive why it won't work.

I've used some large commercial sandblasters cleaning paint and rust off steel, obviously not using walnut shells. I see Harbor Freight with a few small blasters that I could try but I would like to hear a clear explanation why it won't work.

Are you saying the carbon is too soft and won't blast well or are the walnut shells too soft? I'm not trying to argue with anybody, I would just like a clear understanding of your thinking. Thanks

 

I was standing around at my buddy's independent shop. I saw what he had to do with a dremel (or similar) tool to clean out the intake and the back end of the valves on an Audi RS6. I've also talk to the BMW techs who use the "walnut machine" provided by BMW/Mini. I've also witnessed the use of the walnut machine on restoration projects because they can use other methods due to the delicate nature of the end product. Regardless, I can't prove it to you and it's only my opinion based on what I've seen and those who I've talked to. This is the internet, and for all you know, I could be totally full of sh*t I guess.

All I know is from what I've seen, walnuts blow. But that's just my personnal opinion. Take it for what it is. My car had been walnut-ed and still is f*ked.

 

Thanks tominizer, I appreciate your opinion and honesty!

 

Walnut shell blasting is not unique to MINI nor is it particularly new. It is the "go to" solution for a number of manufacturers and is in widespread use for such things as carbon removal. Contrary to one person's opinion, it does work and is in fact much more efficient and effective than trying to remove deposits with a manual procedure.

 

If my car has never had carbon cleaning for 78k AND I have CPO MINI Next, XL warranty AND Maintenance to 100k. Is it possible to get this covered?

Dealer said none cover it and they said it's $600 procedure.. You'd think 1 would, and since it's a maintenance thing it should be under my maintenance plan.

You'd think being around supposedly the best dealers(Prestige, Mini of Mainline, and Ottos Mini) MINI has to offer and so close to Corp office that things would be easier to deal with in terms of ownership and getting things done.

 

Has anyone tried the 3M Intake Cleaning Kit?

 

Before and After dealership walnut blasting photos: https://www.northamericanmotoring.co...10-post89.html

 

Chris,
Thanks for your post!

I was considering doing it myself when/if I need this done. The results look great and the price ($212) seems very reasonable to me. I have the compressor and thought about buying the blaster and shells from Harbor Freight. But for that price, it's not worth the effort.

I guess the only question is whether a dealer near me does this process and at what price?

It looks like you had it done in April, how much improvement did you notice?

 

My Mellow yellow 09 with 34,000 miles had walnut blasting today. Was told unless I used the "right" gas and fuel additive every tank this would happen every 3-4 years (mine is only 2 1/2 years old).
This has been a BMW problem for years and years. Back in my BMW days it was because the engines were designed for European gas and US gas is junk compared to European.
What is junk is that BMW hasn't fixed / redesigned this and they still have this expensive fix needed every few years. Since it is fixed as a warranty item (and not maintenance) it is thus a defect. I'm sure the right lawyer could get rich over this and get us some small bit of relief.
So in 34,000 miles I've had to have front and rear brakes replaced, this fix and several others. I'm beginning to wonder if this is a car I want to keep after warranty expires.

 

It has nothing to do with gas or additives. The fuel on an "S" is injected directly into the cylinders, bypassing the intake valves. MINI's constant harping on "top tier gas" is nothing but "smoke & mirrors" .

There are other manufacturers who have direct injection engines that don't have a carbon build up problem on the intake valves. The problem is in the PCV system's crankcase vapor labyrinth in the the head cover, it doesn't scrub the oil vapor out of the crankcase vapors as it should.

Now that MINI redesigned the PCV system, head and head cover, for 2011, they may have solved the carbon build up problem. Only time will tell.

Dave

 

How do you know if you have Carbon Buildup?

 

You will start to get a lot of hesitation and it will feel like the car is difficult to maintain a constant speed at lower speeds. I noticed 40mph sputtered and there isnt a smooth delivery of power.
Im planning in doing a full ported/polished head treatment when i reach 100k. I blocked off the pcv hose on my 2007 and put in an OCC after i manually cleaned the valves and it made a big difference. I put together a How-To on cleaning the valves in the How-To section. Its a good afternoon project.

 

occ ????

 

I had my valves cleaned with walnut shell blasting and I've been trying to get MINI guys to get it done at my friend's shop. He's located in SoCal, so if OP is nearby, I definitely think you should pay my friend's shop a visit. If the chief editor of European Car Mag comes in on a regular basis to work on their longterm vehicles, you should too!

The before and after shots are from my engine with 40k miles. I don't drive overly aggressive and nor did I ever track the R56 up to that point, so I hope after seeing the pics, it compels others to get this done.

https://www.northamericanmotoring.co...cal-ltbmw.html

 

Oil Catch Can

 

I just built my own walnut blaster machine and completed the job over the weekend. I can say that just using the walnut blaster is not going to remove all the really baked on carbon on the backside of the valves. I had to use my borescope and manually pick the carbon off, that the walnut shells couldn't remove. And after three walnut shell blasting intervals eventually had to soak the valves with seafoam and use a brush to scrub the remaining carbon off. After this I did a final walnut blasting to ensure it was a mirror finish. It is not easy but doable. I can tell you that Seafoam by itself will do little if anything to removal the carbon buildup. I would consider this a good preventive measure after the carbon cleaning at some frequency but thinking that just seafoam will solve your problems is not true. I use to have a check engine light and now it is gone. Car runs much better and happy that this is behind me. I am installing the catch can today to stop the excessive amount of oil throughout the entire intake system, including throttle body, intake, hoses etc...

 

I just order the vacuum attachment and wand for getting my Mini done as well. Mine is caked up pretty bad.

What grit size walnut shells are you running. I haven't figured if I should run more course like 18-40 or my regular standby 35-60. Thanks.

Sent from my iPhone using NAMotoring

 

I bought the fine walnut shells from Harbor freight. I went through almost 25lbs of shells during the cleaning process. Did you order from Lisa at Wezag? She just got a shipment of vacuum attachments and wands in from Germany.

FYI- To ensure the valve ports are closed I rolled the car in 6th gear with the valve cover off to ensure I didn't accidentally fill the cylinder up with shells. I also taped off the ports that I was not cleaning with Duct tape to ensure no shells went into an open port. When you remove the wand from the vacuum attachment, the vacuum will pull shells through the walnut shell feed line and spill a little. Just remember to lay the valve cover over the head to ensure you don't get shells on the cams etc...

BMW procedure recommends 20/30 SAE or 0.45-0.80mm walnut shells. They can be sourced through www.marcousa.com or Trinity Tool Company www.trinco.com I just used fine walnut shells from Harbor freight to due to convenience and cost.

 

I got my tools off ECS tuning. The walnut shells, I get them at my local contractor supply shop, they have a decent selection of sandblasting media.

I just have to figure out how to check if the valves are closed.(Mines a Auto) I'm a total idiot when it comes to how a engine internals work, but let me know if I'm wrong. If the 1st cylinder intake valve is open the other 3 should be closed right? Thanks for your help.

 

I did not pay attention to the relationship of multiple ports and if the valves were open or closed simultaneously. There are two valves/port. Each valve set in each port opens together as the cam rotates. I focused on one set of valves for each port and taped off the other ports for blasting. You may need to research how to rotate your engine without starting it (jumper with switch to starter) since its an automatic. With a keyless start it can be a little difficult to rotate your engine in small increments needed to ensure the valves are closed. If you wire up the jumper on the starter you should disconnect your spark plugs and take off the valve cover. If you are removing the valve cover it is easy to see where the cam lobes are positioned. It is a good time to replace the gaskets that leak in the center of the valve cover. Do this for each port and take your time.

 

Great post, thanks for the helpful pictures.