Walnut Blasting

[BadgerDog]

So I understand the idea behind it and what it buys you, etc. I'm just trying to get a feel for how often. I have to assume its never been performed on my car, which is a 2016. Is it about that time, or too early to be wasting money on it? A QUICK search found one place that will do it for $250, and it sounds like something I could do myself (already have a nice air compressor, would just need a blasting tool, which is cheap enough). Possible I could find it cheaper elsewhere, but regardless, what say the collective?

 

[Smartbear]

So I understand the idea behind it and what it buys you, etc. I'm just trying to get a feel for how often. I have to assume its never been performed on my car, which is a 2016. Is it about that time, or too early to be wasting money on it? A QUICK search found one place that will do it for $250, and it sounds like something I could do myself (already have a nice air compressor, would just need a blasting tool, which is cheap enough). Possible I could find it cheaper elsewhere, but regardless, what say the collective?

What model z4 have you got? Not all of them need walnut blasting
Rob

 

[BadgerDog]

2016 Z4 sDrive35i. Estoril blue if the color matters. (Kidding, haha)

Joking aside, I was under the impression that all of the fuel injected engines can end up needing it because they dont get fuel washing over the valves. Wouldnt that be ALL of the zeds?

 

[john-e89]

So I understand the idea behind it and what it buys you, etc. I'm just trying to get a feel for how often. I have to assume its never been performed on my car, which is a 2016. Is it about that time, or too early to be wasting money on it? A QUICK search found one place that will do it for $250, and it sounds like something I could do myself (already have a nice air compressor, would just need a blasting tool, which is cheap enough). Possible I could find it cheaper elsewhere, but regardless, what say the collective?

What size is your compressor Badgerdog...? Unless you’ve got something with at least 200litres with up to 145psi capability and a flow rate of around 12 CFM you’ll not do it I’m afraid AFAIK, that’s what you need for soda blasting for example so I’m assuming it’s the same for walnut too. These things chew air like you wouldn’t believe.

 

[BadgerDog]

Oh dang. If the needs are really that high then I'm out. Its decent but not that good (cant recall exact specs off hand though).

 

[Zikim]

You can always use CRC Intake Cleaner as an alternative method, remove intake manifold as per walnut blasting but then use a strong chemical that dissolves the carbon build up. I did it earlier this year and it works a treat. It is detailed on a previous thread on here
https://z4-forum.com/forum/viewtopic.php?f=23&t=120044&p=1717627&hilit=valve+cleaning#p1717627

 

[DMike]

2016 Z4 sDrive35i. Estoril blue if the color matters. (Kidding, haha)

Joking aside, I was under the impression that all of the fuel injected engines can end up needing it because they dont get fuel washing over the valves. Wouldnt that be ALL of the zeds?

As far as I’ve read, not necessary for the M54s. Or perhaps for them just find a nice long winding road through a forest with walnut trees, then blast until valves are red . When I first time heard ”walnut blasting” this instant Schwarzwald association was the first one that came to my mind...

 

[R.E92]

I had it done a few years ago at 50,000 miles at a BMW dealer while in for warranty work, they said the valves weren't that dirty to begin with. Total cost was £250 which included all replacement gaskets.

I almost always prefer to DIY but £250 is the going rate even at specialists so at that price it seems a no brainer to farm it out. The cost of buying all the equipment means that unless you are going to do multiple vehicles it doesn't save any money.

 

[Chippie]

I’d say the valves would need doing about every 60,000 miles as mine we’re getting quite a build up by then

 

[MACK]

You only really need to be considering this on DFI engines where the valves aren't fuel washed by the injectors, which eliminates all the E85 variants and only leaves the turbo E89's. I'm led to believe the older N54/5's are worse in this respect than than N20 due to the design of their breather systems, but none of the BMW engines are as bad as some VW/AUDI ones

 

[Zikim]

I’d say the valves would need doing about every 60,000 miles as mine we’re getting quite a build up by then

If you fit an Oil Catch Can after cleaning the valves you will never have to do it again because you are eliminating the source of the problem

 

[bg1]

What is walnut blasting? Is it Apr 1?

 

[Smartbear]

What is walnut blasting? Is it Apr 1?

It’s the use of ground walnut shell as a medium for blasting carbon build up from the intake valves/ports
Rob

 

[mcbutler]

Oil catch can is a must, I fitted the mishimoto kit earlier this year after reading comments by multiple performance suppliers/tuners that it is the first step with any direct injection engine.

My post on fitting to 35i is here ....

https://z4-forum.com/forum/viewtopic.php?f=23&t=119149&p=1705789&hilit=oil+catch+can#p1705789

 

[BadgerDog]

As far as I’ve read, not necessary for the M54s. Or perhaps for them just find a nice long winding road through a forest with walnut trees, then blast until valves are red . When I first time heard ”walnut blasting” this instant Schwarzwald association was the first one that came to my mind...

:rofl:

 

[BadgerDog]

I have an oil catch can on order already, as it so happens! I found a very nice aluminum piece to hold it to the large strut in the engine bay here:

https://www.amazon.com/gp/product/B0714CYKBJ/ref=ppx_yo_dt_b_asin_title_o02_s00?ie=UTF8&psc=1

Quite cheap, and incredible quality for the price.

Ironically the catch can is not legal in California. Which is bloody weird because if I understand correctly it should actually reduce emissions a slight hair by keeping oil out of the combustion chamber? I guess its just "ANY modification is unacceptable, regardless of whether its good or bad, if our corporate masters havent paid us to allow it". Sometimes this state really sickens me TBH.

Since I am only at 40k miles (only 3 of those mine... so far) it sounds like it could be a touch early still from others' experiences. And the oil catch can should slow additional buildup to a crawl (as long as I remember to empty it regularly, this is a new thing to me). So I'll likely have it done someday when I get around to it just to get back to like new condition and then rely mainly on the catch can to do its job.

[ref]Zikim[/ref], thanks for the tip on the cleaner, I will check that out as well when the time comes. That could definitely be a DIY option. I wonder what the effect is on downstream components (Cat, etc) of running all that broken up fouling through the engine, though, as that is where it will ultimately end up going, unless there's a nuance I am missing.

 

[R.E92]

You want to fit the catch can to the low pressure side if you want to reduce carbon buildup. Most will just fit one to the high side which only catches a fraction of the blow-by.

 

[BadgerDog]

You want to fit the catch can to the low pressure side if you want to reduce carbon buildup. Most will just fit one to the high side which only catches a fraction of the blow-by.

OK, thanks. I'll dig into that some more and get a better feel for whats where.