ORIGINAL: Ed_Moorman
I've had 4 OS .46AXs and still have 2 of them. Outstanding engines.
It sounds to me like it is too wet when you start it. I hand start all my 2-strokes and have never needed a starter on the AXs. Choke your engine as you normally do and turn the prop so the piston it up against compression where you normally would flip start it. Hook up the glow ignitor and take the spinner with your right fingers and snap it backwards. The piston will go down, then back up and hit compression as if to start backwards. Since the cylinder is a little wet from the prime, it will fire prematurely and start forwards. If you don't have a spinner, spap the prop backwards. I use a glove. In no case should you pull the prop through compression and top dead center. To do so will cause it to fire backwards and attempt to get your finger.
Hrm...I'll try bouncing it off compression next time. It's proven to be able to do so, when it starts backwards I trim the idle down to an unstable but still running point and it will bounce itself over in the correct direction fairly quick. I will admit I probably have it set a bit rich. Habit from the cars where if you peak them out they overheat in half a tank I guess.
Oh, and it does, indeed, have a spinner.
Set the high end needle to peak and back off 4 clicks or more. Idle down and time 30 seconds, then pop the throttle to full power.
1. If the engine rumbles and blows smoke, it is too rich.
a. Close the low end down 1/8 turn and try again.
b. Keep doing this until you can go from idle to full power without and stumbling.
c. At the end of your adjustment you may need to turn the low end adjustment only 1/16 turn.
d. It is better to be slightly rich than to be a little lean on the low end.
e. As fuel burns down in your tank, the engine will lean out slightly and you don't want it to overheat and kill a glow plug.
2. If the engine coughs and spits, it is too lean.
a. Open the low end adjustment 1/8 turn and try again
b. Keep doing this until you can go from idle to full power without and stumbling.
c. At the end of your adjustment you may need to turn the low end adjustment only 1/16 turn.
d. It is better to be slightly rich than to be a little lean on the low end.
3. This takes a while so don't be rushed.
4. I use 10% Omega, castor blend for my OS engines. It is my opinion that the ABN, nickel plated OS sleeves need some castor oil for long life.
5. I like the OS A3 plug. It is now called the OS #6.
6. An 11-5 is my preferred prop for sport flying on my OS .46AXs. It revs up good and pulls well.
I'll print this out next time I head out. I've had really good luck with the OS #8s myself, and I am using 15% Odonnel aircraft fuel. 18% total oil content, and judging by the slime on the side of the fuse and right gear when I shut down, quite a bit is castor.
ORIGINAL: downunder
ORIGINAL: aspeed
(A) would be 13,200 rpm.
I just recorded the peak rev sound at about the 1:20 mark then trimmed it to a period of 0.1 secs so I could count the individual firing impulses. There were 22 in that time which works out to be 13,200 revs.
....Damn. I have but two things to say.
1: You have some really good equipment and a well trained ear to be able to determine the RPM I'm getting from the audio my cell phone recorded.
2: My ear isn't as off as I thought it was, that falls right in the middle of the range I guessed it to be in.
Just out of curiosity about what kind of RPM should I be getting on 15% fuel and an 11x5 prop?