WTD: Ultrasonic Carb Cleaning (CB400F)

[ManicGTI]

Hey all, i've been away for quite a while as my 400 has been laid up in storage following a housemove.  I've just managed to get it back so onwards I can go again...

Does anyone have any recommendations for Carb cleaning services?  (Ultrasonic) I'm not sure it's the direction i'll be going in yet, but i'm fed up with rebuilding them, and I don't think I'm getting fuel through.  I'm worried that my 'hand' clean wasn't enough and the internal pathways are still blocked.

Thanks,

Dave

[mike the bike]

it's cheaper to buy an ultrasonic bath from ebay and do it yourself.  I bought a 2 litre one, which is OK for doing them one at a time.

[Chris400F]

I'm sure Julie had hers done some time in the past but can't find the thread. If she sees this she may be able to tell you where she went (as opposed to telling you where to go ....).
Consensus from the thread I did find was not to split the bank of carbs unless absolutely necessary.

[Nurse Julie]

I had mine done when still living down in Kent Chris. Not a good experience, the plonker put some type of corrosive/ caustic cleaner in the bath and the carbs were left with a nasty white powdery residue. I tried every way of cleaning out that white stuff but it kept leaching out of the metal and reappearing. Make sure whoever cleans them uses something very gentle, something non corrosive like screen wash. I did get them clean enough eventually to put them back on the bike but they were far from perfect. Luckily, I didn't have any problems with blocked jets etc. By the way, the chap did give me a full refund !!!!

[AshimotoK0]

I think US cleaners are OK but not the 'cure all' for carbs that some people proclaim they are. When you get those white deposits that Julie had it's usually by long term standing with rainwater getting inside and my experience is that it is not removable by ultrasonic cleaning. What they are good for is reaching internal drillings etc that are inaccessible due to being 'blanked off' by the carb manufacturer after drilling. Sometimes you can't beat a good old dunk in methylene chloride but this is now  outlawed by the H&S brigade (still available off eBay though ) . Plus those white corrosion deposits are only really removed with mechanical abrasion, soda blasting being the preferred method. Someone else is bound to chip in but I do have lots of experience with US cleaners as I own a 45 litre one myself and we have three even bigger ones where I work. All of them are industrial versions 40kHz. My experience of the Chinese ones is that the build quality is poor so be careful and run from an RCD protected mains supply. Also, someone gave me a small Chinese one to fix and when I got it working I did the standard test of putting a bit of aluminium foil in it and checking for tiny holes in it after a couple of minutes (caused by the cavitation). With that Chinese one the foil disintegrated to dust withing a few seconds, which obviously proved that it was working, but far to aggressive for delicate alloy parts. Also you need the correct fluid for high zinc content alloy used on carbs. Allendale electronics sell the correct stuff on eBay. If you use stuff that is slightly alkaline or acidic, you will end up losing the iridescent finish from the alloy and you can also get horrid black deposits on the alloy.

This site is a great resource for advice & info !  http://www.cb750carbs.com/

[Chris400F]

When you get those white deposits that Julie had it's usually by long term standing with rainwater getting inside ...

Maybe, but the deposits Julie had the problem with were as a result of the cleaning and whatever additive was used.
http://www.sohc.co.uk/index.php/topic,7816.0.html

[ManicGTI]

Thanks for that link, interesting site!

So it's the internal drilling that I am concerned about.  The net seems to have mixed opinions of self-US cleaning, and I'm not keen on spending much on a cleaner for one project, esp if it's not an appropriate cleaner!

I have previously stripped, cleaned (by hand) and rebuilt all four.  They are now sitting with replacement Jets, Needle Valves, O-Rings etc (after a few rebuild attempts eliminating various leaks!).

History: http://www.sohc.co.uk/index.php/topic,9575.0.html

[SteveD CB500K0]

It's years since I last spoke to Mike Nixon.

Actually, it's 11 years!

His website hasn't changed much 

I'll see if I can get him to join us here.

Steve

[Derckey]

Had mine done by George from http://www.icmhome.org.uk/

Was happy with the result

[Derckey]

Forgot to mention - he is based in Penge, South London

[ManicGTI]

Oh awesome,thanks!  I'm also in South London now!

[Laverda Dave]

I can recommend icm in Pence. Very good service and they know what they are doing with bike parts.
I was charged £25 per carb.

[paddyz1]

Before you spend any money why not try and boil them. That may free any gunky fuel in the orifices. Then you can clean out any residue with air and carb cleaner

[tom400f]

Dave - do you still need my valve spring compressor?? 

[ManicGTI]

   Apologies, Tom, yes I do still have them!