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Does anybody know a good process to set up the AeroCarb? My Sonex, with AeroVee engine, is ready to fly, but I am afraid of this carb because of erratic running, having to dance on the mixture and hard throttle (physical) application after reducing the throttle (it is not the cable. I have heard this is caused by vacuum). This thing has to be dangerous and I am sure causes a lot of problems. If anybody knows the secret to using this thing, I would love to learn it. Thanks

Things accomplished:
Read manual and worked with AeroConversions and followed instructions
Checked fuel supply - no issue
Checked induction system for leaks - no issue
Checked timing - runs the same on both ignitions and no drop between them
Tried #1 and #2 needles - similar results
Runs good at high RPM. When going to idle have to lean for smooth running (is this normal operation?)

I fear that you may have just kicked a hornets nest with those words... However I think most would agree that it begins with following the Aerocarb owners manual as published by Aeroconversions.

The biggest and best piece of advice you'll get here is very simple: read and follow the manual's directions!

I'll let you in on a little secret. The poor, overworked guys at the factory get a lot of calls dealing with AeroCarb/AeroInjector setup and tuning. People seem to read reports and rumors online and for whatever reason, that trumps the written directions. DON'T FALL INTO THAT TRAP!

The AeroInjector is a simple fuel metering device. It is not properly tuned at the factory (they can't...each engine is different) so it's up to the builder to set things up correctly, but if you follow the directions you'll be rewarded with a reliable setup.

Go to the Aeroconversions website, download the manual, read through it then use it to adjust your engine, and we can go from there. Please let us know what specific questions you have.

Thanks and be safe!

Rynoth wrote:I fear that you may have just kicked a hornets nest with those words...

Literally.

Please follow the written manufacturers directions and share any concerns or problems you have.

Your first point of contact should ALWAYS be the factory tech support team, but words like "dangerous" won't help and are not specific. Getting out of bed in the morning can be considered dangerous.

I will have to second the READ AND FOLLOW THE DIRECTIONS a advise. I have followed the directions and plans and have had great success with my build so far. If somtthing does not make sense to me I send a note the Sonex/aero conversions tech support. They have been great at responding quickly and making sure all my questions or concerns are addressed. Yes you kicked a hornets nest.

Where are you located? Maybe there is somebody local that can stop by and help you get it initially set right.

Keith
#554

The database says he's in Kenly, NC. , near Raleigh. Lots of Sonex owners in that area. I'll bet one of them can fix that "dangerous" carb.

I have followed the manufacturers manual and I have contacted AeroConversions and followed their email, which was different from the manual, but still not much success (not where I feel it is reliable). I have talked with a Sonex owner in the area, but he trashed the AeroCarb and installed fuel injection. His runs like a Lycoming - nice.

If there is somebody within range of Kenly, NC (Raleigh area) that can come help, I will be glad to pay expenses. Further, if there is a test pilot that will come fly it after his inspection, I will be glad to pay expenses.

I would very much like to hear and witness success with this product. I have a lot of time and money invested.

While you search for a fellow builder in the Raleigh area to assist you with your AeroCarb there are a few things for you to consider. You should also know that my Aerovee runs better than a Lycoming - really.

The first start of any new engine is an experiment. It takes patience to properly tune and configure an engine. What type of engine do you have?

What I have posted here is all in the Aerovee and AeroCarb manuals but your focus may be unjustly on the AeroCarb. First I am assuming you have some type of VW engine conversion. In tuning an engine with an AeroCarb you also need to consider the ignition timing, induction leaks, air intake, camshaft alignment, and fuel system. A problem with anyone of those items can potentially make you think you are having problems with your AeroCarb. For instance, make sure your fuel line routing is to specifications. If you have a bunch of ups and downs in your fuel line you could have air bubbles trapped in the line or it could cause restricted fuel flow. Also, make sure your filter screen and fuel filter are clean and that there are no sharp bends in your fuel line restricting fuel flow. You also want to make sure your fuel is clean and free of water. Follow EAA's and FAA's guidance on verifying proper fuel flow.

There are other things that can cause a poor running engine such as improper camshaft alignment with the crankshaft (this has happened to more than one unsuspecting builders and they did not discover it until first start), or you could have your ignition trigger magnets installed backward as a few builders have done. I know of one builder whose camshaft alignment was off by a couple of gear teeth. The engine ran, but ran kind of like you describe your's running.

A dirty air filter can cause difficulty setting your AeroCarb properly.

Leaks in your induction system can cause a poor running engine too. Make sure your intake elbows are properly sealed and seated. Make sure all the hoses on the induction system are tightly secured. I had an induction leak and never even considered that a possibility when I first set up my engine until I called Sonex and they suggested I double check for leaks.

If you set your AeroCarb to the initial settings specified in the manual, the engine (with everything else properly configured - timing, camshaft, fuel system, etc.) should run fairly decently (i.e. stock needle, with proper side up, and lined up as shown in the manual). After that the primary adjustment you will make is to the mixture needle setting.

I wish you the best of luck and look forward to seeing you in the air! Please keep us posted on your progress. Hang in there, you will get this all sorted out. Just be patient and methodical (try one thing at a time). Even factory engines are tricky to get properly set up. Like everyone else here has said, follow the manual to the letter and work with the Sonex Tech support crew, they know what they are doing. Most of all be safe.

ntust out of curiosity you mention your problems at idle. What rpm are you idling at? A new aerovee doesnt like to idle much below 1000 rpm until it is well into the break in period. I would also look at the timing. Do you have the same issues when on the primary or just the secondary? Finally, what do you mean by hard throttle? Is the throttle physically hard to move or are you referring to something else? Don't give up. With enough information I'm sure the problems can be figured out

Keith
#554