Hi All,
I have fit a YS DZ 170 into a Black magic and have been struggling to get everything running this season so far. After a few setup errors, I finally got the engine to start up, but it only runs for a few seconds and then very abruptly dies. I also tried to bump the throttle a few times and that always was met with a strong ending that appears to backfire as the spinner was knocked loose.

I am running a 19X11 APC, on Cool power 20% heli fuel

Before start of this season, I sent the motor to Richard at YS performance and had him replace anything not up to snuff (new pump diaphragm, new read main bearing) and run the motor to insure it ran OK

I did not touch anything during these attempts, other than to start with the high end needle to between 2 and 3 full turns out

The backfire leads me to believe I am lean on the low end, but I am not very experienced on these engines - I know there is a regulator screw that functions somewhat as a low end mixture - The screw is currently flush with the housing, per Richard's suggestion and the way I got it

I have not been able to get the motor to run more than 5-10 seconds without loosening the prop, or spinner accompanied by an abrupt end each time

Any suggestions out there? - I really want to make a go of my older 2 Meter ship on glow - just for sport flying

Thanks to all who respond