Ignition or Carb problem

I found the problem. The fuel level was set too high on the rebuilt carbs. Adjusted the carbs and now my plugs are good, no black soot on the landing gear or the belly of the airplane, and it does not run rough when pulling the rpm’s back for landing. I also found the vent lines were run all the way to the bottom of the cowling. I cut those down to about 4” and tucked them behind the bowl clip. I finally can enjoy fly the airplane.

I sure hear quite often about mistakes made by people who rebuild/inspect carbs. So many times people send in their carbs for service and when they get them back they have engine issues. These poor souls sometimes spend many, many hours and dollars troubleshooting everything they can think of, usually assuming the problem can't be the carbs because they were just inspected and refurbished by some supposedly reliable shop. Then after all this time and money has been spent, it turns out that the carbs were messed up or problems were not found by the shop.

Because of this history, I have not sent in or disassembled my carbs every 200 hours as recommended in the Rotax maintenance manual if they are working perfectly; I believe in going "on condition". My carbs now have 500 hours on them and have never been touched (other than annual syncs and float bowl removal and float weighing) and they are still working perfectly. At some point I know I will need to send them somewhere for service. I am very interested in hearing what shops have proven to be reliable and nearly mistake free?

James,

Earlier in the thread Eric said the following, which seems to indicate he installed the floats himself.  So maybe we can't blame a shop this time!

"Installed new plug wires, cleaned both carbs and installed new floats. Synced carbs at 4000 rpm, 3000 rpm and 2000 rpm all good there. 12- rpm drop on both mags at 4000 rpm. It still idles like crap and the exhaust pipe leaving the muffler is full of black soot.  I am about to remove the muffler and see if it is one cylinder that is running rich making the exhaust black. After that I think I’ll. Give up on this engine." 

I have seen some carbs not properly overhauled and then its time to trouble shoot. If you just put your carbs back on the plane and it's acting up and it wasn't before you had them overhauled then I'd pull them back off and find out what isn't correct. 

I do lots of carbs every year. I don't have any issues. My fee is $500 and $20 for shipping. I have a one day turn around. If you have any questions about carbs please feel free to call.

p.s.

James,

How old are the 500 hour carbs?

Roger, my 500 hour carbs are about 3 1/2 years old. Do you think I am taking undue risk by going "on condition" and skipping the 200 hour inspections? I value your opinion.