Cleaning carburetors

Hi Alejandro

The reason that Bing carbs should not be cleaned with Ultrasound is simple.  Bing, like a number of fuel system suppliers, use epoxy sealers on  passageway bores. These can be seen on the carb as a clear sealer on small sealing "balls" that are pressed into the drill bores for passageways in the carb bodies.  Ultrasound can loosen the sealer and then you have a very difficult air leak to troubleshoot later.  Many carb sets have been ruined by this cleaning method and it is not recommended.  

Cheers

That's very interesting. I know that my carbs were ultrasonically cleaned in the past - by the official Rotax service agent at that time - and in cleaning them recently looking for the source of some rough running just above idle, I saw that the sealer over some of the balls was peeling.

I've scraped and cleaned all of them and put fresh epoxy on. Should that be OK or is epoxy put on the balls before they are tapped/pressed in?

No improvement in the rough running BTW!