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I’ve got a Waiex a model and as a glider pilot I always land from downwind to landing with the engine at idle. I never count on the engine to get me to the runway. I’ve been trying to get the aero carb dialed in and had the engine quit multiple times but moving the mixture to the right spot and cranking always started it.
I’m installing the turbo now and going to change my needle from a 2.5 to 3.0 because from idle to full throttle I’ve always had to enrich the mixture to keep it from dying.

jerryhain wrote:I’ve been trying to get the aero carb dialed in ..... I’ve always had to enrich the mixture to keep it from dying.

The techniques that are described in this post worked for me: http://sonex604.com/aerocarb_thoughts.html

Hi Jerry,

jerryhain wrote:I always land from downwind to landing with the engine at idle.

Yep, that's the way I was trained. Always make sure you have the runway made before reducing throttle to idle abeam the numbers. My power out landing was a total non-event. I later thought of all those guys flying "airliner patterns" and how a similar event could have been tragic if I had been taught to fly that way.

Wes

It is important to remember that with an aerocarb or aeroinjector fuel will flow (and can leak out the bottom of the airplane) whenever the main fuel valve is on and the mixture is not totally leaned (off). That is why my starting procedure (aerovee engine) starts with the mixture at idle cutoff. Starting from everything off, the procedure is: 1. Main fuel valve on. 2. crack throttle about 1/8 to 1/4 inch. 3. press and hold starter button. 4. slowly push in mixture until engine starts. 5. release starter button. After engine start I have to back the mixture out about 1 inch, because that is how my aerocarb is set--it runs rich. For a hot start it won't start unless i give it more throttle while cranking, about 1/2 throttle, in which case be prepared for the startup and ready to back it back down before you run into something.

When I first got the airplane it had vapor lock issues. My first few landings, when I would pull the throttle back to idle the engine would just quit. So, I had a few dead stick landings. Then, I learned to leave the throttle up to about 1500 rpm to land. Then, many times it would quit when pulling it back to idle during runout on the runway. (I actually got embarrassed a few times). Once we got the vapor lock issue solved, it was ok, and has been fine since, but I keep the idle set to 1000 rpm and out of habit try to keep the rpms up over that all the time.

I have not tried to stop and restart the engine in flight. My mechanic tried that without success and had to land on the highway. But, I expect the hot start procedure should work if you are prepared to use it. Just be sure to have lots of altitude and a runway near by in case it doesn't work.

Ron

jerryhain wrote:I’m installing the turbo now and going to change my needle from a 2.5 to 3.0 because from idle to full throttle I’ve always had to enrich the mixture to keep it from dying.

Getting a bit off topic at this point, but when it comes to the 2.5 to 3.0 needle, does it actually change the "curve" of fuel mixture, or just provide more fuel at all power settings? I'm very familiar at this point with needing to lean the mixture at low settings and enrichen at high settings using a 2.5 needle in the turbo, I'm just wondering if the 3.0 needle actually addresses that issue.

EDIT: off topic aeroinjector needle conversation was moved here:

viewtopic.php?f=21&p=42021#p42021

I have accidently turned off my master, a keyed ignition switch which turns with very light touch, in flight. Of course the engine kept running because the primary was still energized. I actually didn't notice it at once since my scan was outside the cockpit. A few seconds later I noticed the digital displays were off and then turned the master back on. After that I decided to put a guard across that area.

Also, I will eventually be replacing that light duty keyed ignition switch with another one which requires more force to turn.

Here's a pic (taken during the building process) before the guard. I don't have a pic with the guard.