loose aerocarb needle

[Johns]

Doing a little cleaning on the motor, inside the aerocarb I put my finger on the needle from underneath and it was loose. Just curios if this is normal or should I be concerned. The throttle was wide open. John

[Area 51%]

First off, you have my condolences on being the owner of an Aerocarb/injector. I did not have a warm and fuzzy experience with mine.

Any movement of the needle in or out of the slide should probably be addressed. A slight "rattle" is normal, however.

[Johns]

Thanks, it does not move back and forth it just has that slight rattle to it. The only problem I have with it is the "burps" which would be nice to find a solution to, and I don't even have the infamous gascolator.

Cheers, John

[WesRagle]

HI John,

Don't know if you have read this yet. If not, it might help.

https://sonexbuilders.net/viewtopic.php?f=65&t=5586&p=42337&hilit=burps#p42337

Good Luck,

Wes

[Johns]

Wes, I have read that but the problem is still there. It's annoying and a little scary. I will continue to keep working on it.

Thanks for the input! John

[Onex107]

My experience with the AeroCarb/AeroInjector in my Onex. When the slide is wide open the thin end of the tapered needle is in the orifice so it will be loose. The initial problem was the play in the ball socket needle holder. It amounted to approx. a half turn of the adjusting screw. That needs to be tightened up. The burp issue can only be solved by insulation, insulation, insulation. Also in my case, after a flight, with the engine heat soaked, on taxi, the engine was surging. Going lean then rich. I added a blast tube to present outside air to the AeroCarb body and like magic the surging stopped on the next flight. In the Onex the only air that goes to the rear of the engine is through the cylinders. I had a coil and voltage regulator failure that I attributed to heat so I added a NACA vent to the lower cowl to admit some outside air behind the engine. It did not change the engine cooling temps. Only time will prove it successful. Sorry to say I just sold my 355 hour Onex to a man in Canada. N2107X is now retired.

[Arjay]

Johns:
I had the aerocarb on my legacy sonex for a few years. Initially, the needle was loose, with about 1/2 turn play on the adjusting screw. I solved this issue by cutting the edge off a small washer and wedging it into the adjusting screw notch so it took up all the play. That solved that problem.

I also had the "burps". In fact it was so bad the engine stopped dead when I pulled the throttle back on downwind on my first flight after buying the bird (very exciting). The burps continued for several months, causing the engine to die when I pulled the throttle back to idle, mostly on landing. (It is very embarrassing to have the engine die before exiting the runway at a controlled field). The first solution to that problem was to cover the exhaust pipes and gas lines with insulating material and route a blast tube from the left naca duct in the cowling to the fuel line. That solved the problem.

This past year we made the final solution; we converted the aerocarb to a Rotec TBI and installed a "burp" tube routed from the Rotec up to and connected on to the fuel vent fitting at the top of the fuel filler neck . And, after some internal modification to the Rotec tbi, found necessary to correct a manufacturing defect, the bird now runs like a scalded dog.

Ron
Legacy Sonex td, aerovee

[Johns]

Hey everyone, thanks for the advise, will keep working on it.

John