[MrBen]

Originally Posted by Russbmw

Can someone enlighten me as to what all the excitement is about this "walnut blasting", and why people with what I'd consider low mileages (50k miles) are having it done?

I've never done anything like this on any BMW I've owned, and all my others had covered a lot of miles.

The issue only exists on cars with direct injection - not just BMW products. In a conventional injection car where the fuel goes through the inlet port, the fuel itself helps stop deposits there. In a direct injection car the fuel is injected straight into the combustion chamber and from what I've read there doesn't seem to be any process in place to stop the intake coking up.

Hence my old E46 330i had done well over 150k without any such issues, but current direct injection E90 325i is on 80k and it appears coking is the problem, hence the interest in the walnut blasting which appears the easiest way to remove it.

[LDNMaster]

Does anyone know if these independants are removing the cam cover to carry out their cleaning?

This takes 3 and a half hours on its own and would require the injector teflon seals and buffers to be replaced on refitting. The reason is that if you don't remove it and block the ports that lead in to the cover then the crankcase breather system could get filled up with walnut shells which will probably cause more problems than the valves being clogged in the first place!

[zltm089]

Originally Posted by LDNMaster

Does anyone know if these independants are removing the cam cover to carry out their cleaning?

This takes 3 and a half hours on its own and would require the injector teflon seals and buffers to be replaced on refitting. The reason is that if you don't remove it and block the ports that lead in to the cover then the crankcase breather system could get filled up with walnut shells which will probably cause more problems than the valves being clogged in the first place!

Very interesting and important point! Thanks for posting and the heads up!!!

[zltm089]

Originally Posted by LDNMaster

Does anyone know if these independants are removing the cam cover to carry out their cleaning?

This takes 3 and a half hours on its own and would require the injector teflon seals and buffers to be replaced on refitting. The reason is that if you don't remove it and block the ports that lead in to the cover then the crankcase breather system could get filled up with walnut shells which will probably cause more problems than the valves being clogged in the first place!

Can anyone find out?

If they say no for whatever reason, then I wouldn't trust them...

[lolololol]

Lots of talk but has anyone pressed the button with these guys yet ?

[Phil325i]

Originally Posted by LDNMaster

if you don't remove it and block the ports that lead in to the cover then the crankcase breather system could get filled up with walnut shells

Erm are you sure? In all the articles and posts I've read on walnut blasting this has never been raised as an issue.

As far as I know, the crankcase breather system discharges into pipework that is plumbed into the inlet manifold, not into the ports in the head. In all the pics I've seen there are no holes in the ports that would allow breather fumes to enter. It's all upstream of the head, and would be removed to access the exhaust ports anyway.

Just my five penn'orth...

[LDNMaster]

Pretty sure, I have seen this done in the early stages. I'm having trouble posting a link to a picture of the cylinder head here, but if you search it you can see the ports that enter the cam cover.

You could literally have a shot breather system!

[Josh1a1h]

Originally Posted by LDNMaster

Pretty sure, I have seen this done in the early stages. I'm having trouble posting a link to a picture of the cylinder head here, but if you search it you can see the ports that enter the cam cover.

You could literally have a shot breather system!

Any update on getting walnut blasting done at battersea? Or is this still new news? I mentioned it to Monty but he was unsure what I was talking about

Still waiting for a quote

[Matthewricha]

Got my car booked in for January in Camberley. Hope it sorts out my hesitation and lumpy throttle response.

[phil200tdi]

The point of using walnut shells is that they are combustible. If any dust is left in the port it will quickly get burnt off as part of the combustion cycle.

[Tichx]

I've used TWG before for my USB Retrofit and Alpine Retrofit, top indy garage, Will is very knowledgable and helpful.

I've also had a service from them and introduced a couple of friends, all are happy...

I've recommended them on here before, good to see others are as well, reasonable prices and their workshop is in a industrial estate which has ample parking and overnight facilities, here's the website link:
http://www.twgautomotive.co.uk/about.php

I'm actually seeing Will next Friday, I will ask him what machines they use for this valve cleaning..

Regards,

Tich.

[seanblee]

Just been quoted £580 inc VAT for this by Sytner Chigwell Think I'll be giving that a miss!

[Drrncour]

Originally Posted by MrBen

Has anybody had this done at this garage as yet? (or even used them for other things?) I presume cost for a 325i (N53) would be the same as a 335.

Mine is getting very juddery at idle when cold and is hesitant when pulling away, which sounds a lot like this problem, and my BM dealer wanted £200 just to take the inlet manifold off to see if this was the issue!

Only cost me £260 to have the job done on a 325i at a main bmw dealer, and your local also.

[seanblee]

Originally Posted by Drrncour

Only cost me £260 to have the job done on a 325i at a main bmw dealer, and your local also.

Which dealer was this, please? Thanks.

[Drrncour]

Originally Posted by seanblee

Which dealer was this, please? Thanks.

Just rechecked the invoice £277 total inc vat. Bmw Vines Redhill

[seanblee]

Originally Posted by Drrncour

Just rechecked the invoice £277 total inc vat. Bmw Vines Redhill

Thanks for that. Bit of a trek for me, but I'll keep it in mind if I don't have any luck with more local dealers!

[seanblee]

I despair of BMW dealers sometimes. According to Specialist Cars in Stevenage, there's no problem with intake valve carbonisation on the 335i, so they're not offering decoking as a service. Not taking my car there then!

[zltm089]

Originally Posted by seanblee

I despair of BMW dealers sometimes. According to Specialist Cars in Stevenage, there's no problem with intake valve carbonisation on the 335i, so they're not offering decoking as a service. Not taking my car there then!

There're a bunch of cowboys. I bought my car from their Tring branch. And funnily enough, sent loads of emails to them when I was having carbonisation issues with my car.

If you're going main dealer route, nothing beats Battersea Stewarts rd.

[Tichx]

Originally Posted by Tichx

I've used TWG before for my USB Retrofit and Alpine Retrofit, top indy garage, Will is very knowledgable and helpful.

I've also had a service from them and introduced a couple of friends, all are happy...

I've recommended them on here before, good to see others are as well, reasonable prices and their workshop is in a industrial estate which has ample parking and overnight facilities, here's the website link:
http://www.twgautomotive.co.uk/about.php

I'm actually seeing Will next Friday, I will ask him what machines they use for this valve cleaning..

Regards,

Tich.

Update:

I met Will on Friday from TWG Automotive, here's the update...

for Petrol cars they have a wallnut blasting machine, picture here:
http://www.e90post.com/forums/album....ictureid=49889

for Diesel cars they offer a 'Induction Service', they use BG products and a machine for this (I had this done on my 335D about a year ago), smoother ride after this service...
http://www.e90post.com/forums/album....ictureid=49888

speak to Will from TWG for more info..

Regards,

Tich.

[EhFit]

Anyone know of any garages in North East Scotland who offer this?

[MrBen]

Originally Posted by Drrncour

Just rechecked the invoice £277 total inc vat. Bmw Vines Redhill

Thanks, that sounds more like it. I've also heard some good things elsewhere about Vines in Redhill, and my experiences with another dealer a few miles north of them have become less and less encouraging, despite using them for years. Time for a change methinks!

What were your symptoms Drrncour? Mine seems fine once warmed up but is getting quite juddery and hesitant from cold.

[Matthewricha]

Hi

Had my car at TWG today for blasting. Very happy with the service and the results!

Drove the car back to near Southampton so had a chance to gauge any differences.. well I can say the idle is totally smooth now, whereas before it was uneven and irregular. My main gripe before was the lumpy throttle response and unpredictable throttle with the car feeling like it was breathing through a blocked nose is how I'd describe it. This is now linear and predictable making manual gear changes much smoother. The car now pulls like a train again

Will took time to tell me how it's done and showing me the pictures of before and after. Glad I did it, he said after doing ten 335i's mine was the worse one.

Can recommend TWG!

Matt