Walnut shell intake port cleaning.

[TheRuss]

Hi folks, I've just had the above done at my local BMW dealership and the guy on the desk that I was dealing with intimated that after cleaning they suck all the walnut shell out, but any dust just goes through the engine... Is that right? Sounds wrong to me, else what's the point of an air filter?!

Here's the pics they gave me of the valves after the cleaning. In one of the pics the valves are open, and there appears to still be debris around the edge of the port and on top of the valve stem...

Not sure what to think.







Any thoughts are welcomed.

Many thanks.

[doublevanosrc]

Shouldn't that be cleaned up like with a vacuum cleaner or something??

[Fade135is]

i am no expert, but it looks like you had some walnut shells go through your combustion chamber.

[uberschnell]

I feel sorry for your turbo's and rings.

[TheRuss]

Why my turbos? That's the intake ports after the turbos...

I was thinking that all the dust/shell etc should have been thoroughly sucked out before the intake ports were opened or the intake manifold put back on though, and photo 2 suggests that wasn't the case.

The guy I spoke to made it seem like they sucked all the shell out and just allowed the dust to go through the cylinders. That said, I don't really think he knows what he's talking about.

That second photo worries me though.

Not sure what I should be asking the dealer to do for me. Last thing I want is extra wear and tear or cylinder scoring because they got crap in my cylinders.

[uberschnell]

Originally Posted by TheRuss

Why my turbos? That's the intake ports after the turbos...

I was thinking that all the dust/shell etc should have been thoroughly sucked out before the intake ports were opened or the intake manifold put back on though, and photo 2 suggests that wasn't the case.

The guy I spoke to made it seem like they sucked all the shell out and just allowed the dust to go through the cylinders. That said, I don't really think he knows what he's talking about.

That second photo worries me though.

Not sure what I should be asking the dealer to do for me. Last thing I want is extra wear and tear or cylinder scoring because they got crap in my cylinders.

your exhaust goes through the turbos, to spin them.

[big boost M]

It should not be a problem.the walnut shells burn up in the combustion chamber before it gets to the turbo. Plus, the walnut shells are not abrasive to metal.

[TheRuss]

That's what I was thinking (regarding the turbos) - that the shell would've burnt up before it got into them. However, walnut shell has to be somewhat abrasive to remove the carbon build-up, surely? I also can't imagine it's great if the piston rings slide over it.

There's a reason we have air filters, afterall.

Not sure what I should be asking from my dealer, but I would really have rathered that they sucked every last bit of shell and dust out of there before opening the valves. It's just common sense.

[big boost M]

At my shop I have performed this service several times. The picture with the valves open was probably after they were cleaned, the way a camshaft works you can not have all of the valves closed at one time. You have to turn over the engine by hand at some point to close the other valves. They should be sealing up all the open and completed ports with tape as they go to prevent excess walnut from entering the combustion chamber. The amount of walnut that enters should be minimal, the picture with the seated valve covered in walnut was probably not finished. The final step is to use compressed air to remove the remaining media. I can post some images later.

[HP Autosport]

So what is the concern here?

[TheRuss]

My concern was the dust or whatever it is around the ports in the second photo (where the valves are open) getting in the cylinder.

However, the BMW garage that did it claim that you can never get 100% of the dust out, so a tiny amount will be left around the edge as shown in my second photo. They also claimed that this would be burnt off immediately upon starting the engine, so wouldn't cause any damage.

Does that sound right, or are they just BS'ing me?

[HP Autosport]

Originally Posted by TheRuss

My concern was the dust or whatever it is around the ports in the second photo (where the valves are open) getting in the cylinder.

However, the BMW garage that did it claim that you can never get 100% of the dust out, so a tiny amount will be left around the edge as shown in my second photo. They also claimed that this would be burnt off immediately upon starting the engine, so wouldn't cause any damage.

Does that sound right, or are they just BS'ing me?

They should be able to get much more cleaner than that. It is true not all will be clean up and will burn up right at start-up.

[TheRuss]

Well, at this point there's no way to know if they got more of it out after taking the photos, but as long as it won't have harmed my engine then fine.

[big boost M]

Sounds right. They could've gotten the valve runner a lot cleaner

[n2djazz]

I don't think BMW would risk sanctioning cleaning the intakes with walnut shells if they thought it would ruin any part, and I mean ANY part, of that engine. If walnut residue did ruin an engine, there'd be a class-action lawsuit against BMW of epic proportions. Why? Because me as well as hundreds of 135i owner would have filed complaints with any and every agency that would listen. I believe BMW discussed that procedure many times before giving the go-ahead to make that an acceptable maintenance procedure. Ultimately BMW is in this business to make money. And they aren't going to risk their financial a$$ over something like using walnut media to clean intake valves.

[mike the snake]

I wouldn't worry. They did my car and it did nothing but make it run better than ever.

[drjekl]

Talking to my local bmw dealer, they said they do a chemical clean which forces a cleaning solution into the valves to remove the carbon buildup on the valves and intake.

He said it takes around 4-6 hrs costs $220 and may take a few attempts to fully clear....

Has anyone heard of this method?

Walnut blasting down here in Australia doesnt seem to be the method for removing carbon buildup, and he said they mainly perform this on minis....

[cheshirecat79]

Originally Posted by drjekl

Talking to my local bmw dealer, they said they do a chemical clean which forces a cleaning solution into the valves to remove the carbon buildup on the valves and intake.
He said it takes around 4-6 hrs costs $220 and may take a few attempts to fully clear....
Has anyone heard of this method?
Walnut blasting down here in Australia doesnt seem to be the method for removing carbon buildup, and he said they mainly perform this on minis....

They may use a system that attaches directly to the fuel rail to clean the fuel system out, but that's an injector cleaning, not an intake valve cleaning. Is this what they're talking about?

[drjekl]

Originally Posted by cheshirecat79

They may use a system that attaches directly to the fuel rail to clean the fuel system out, but that's an injector cleaning, not an intake valve cleaning. Is this what they're talking about?

TBH it didnt make sense to me, as he said it cleans intake valves and injectors also and takes approx 4-6 hrs hence why I have raised this to see if anyone knows of this procedure and if it is standard practice amongst bmw dealers

[n2djazz]

Originally Posted by drjekl

Talking to my local bmw dealer, they said they do a chemical clean which forces a cleaning solution into the valves to remove the carbon buildup on the valves and intake.

He said it takes around 4-6 hrs costs $220 and may take a few attempts to fully clear....

Has anyone heard of this method?

Walnut blasting down here in Australia doesnt seem to be the method for removing carbon buildup, and he said they mainly perform this on minis....

They used walnut media on mine. Our cars use direct injection. Cleaning via the fuel rails will do nothing for the intake valves because the injectors inject into the cylinder and not over the intake valve.

[drjekl]

Originally Posted by n2djazz

They used walnut media on mine. Our cars use direct injection. Cleaning via the fuel rails will do nothing for the intake valves because the injectors inject into the cylinder and not over the intake valve.

Yes I understand the basics of DI, I'm just repeating what the service tech told me and attempting to have someone clarify this if they have had this serviced performed on their car...

To me it doesn't sound right either and would be a waste of time, but if the dealer is performing this clean one would think this is under guidance/instructions from bmw hq?

[TheRuss]

Maybe he's thinking of a different clean of some sort - like an injector clean. They charge you a load of money and just chuck some injector cleaner in your fuel tank.

As far as I know, the only way BMW say to clean the intake valves is with the walnut shell method.