I have 3 DLE engines, a 55, 30, and 20. The 55 and 30 run great. I've had no trouble starting and setting the high and low needle valves on them.

The 20 is giving me fits. It initially set up okay and ran well for about an hour total time(7 or 8 flights). Then it began to quit on me, sometimes in the air when power was pulled back to idle and sometimes just about at touchdown during a landing.

Then it began to quit on me about 15 seconds or so after it was starting up and running at about 4000 rpm (warm up phase). When the engine quits, it does so abruptly, just as if you turned off the ignition. It doesn't slow down before quitting or speed up, it just simply stops.

Once the engine quits, it will not restart even if putting the choke on. The only way I can get it to start is by removing the spark plug for a few seconds. Once the plug is reinserted, the engine starts instantly on a hand flip. When I take the plug out I turn the engine so any fuel in the chamber will pour out. There is never any fuel coming out even while spinning the prop (by hand) while the plug is out. The spark plug (CM-6) looks moist though.


I have reset both needles to 1.5 turns out to attempt a fresh tuning. The high end sets nicely but the low end usually quits on me before it can be adjusted.

I'm pretty sure the problem is with the low speed needle but I can't seem to get it set.

Once the engine quits, it back to pulling the plug to get it to start again. I don't know why but removing the plug does something that allows the engine to restart instantly on a simple hand flip.

Any ideas?

Thanks
Mike 48

1 1/2 on the L is too much, start with 1 1/4". Sounds like it's just getting too much go juice on the L. Plug should not look moist. I could ad that if you ran it way rich you may have fouled the plug so if it is still acting up, get a fresh CM-6 plug. (I assume you have canned the factory plug).

Terry
Thanks for the response. I closed the low end and then reset it to 1 and a 1/4 open. Put in a brand new NGK CM-6 gapped at .021. Engine fired and ran. High end was excellent. Backed it down to idle and let it run there for about 30 seconds. Then attempted to lean the needle to see what response would happen. At about a 1/8th turn the engine quit. I let it sit about 10 minutes , reset to ! and !/4 open and it started up. After clearing the engine with a short blast of open throttle I backed it down to idle again. I let it sit there and run for a good minute. The rpm was at about 1700. It would take full throttle without hesitation and didn't quit on me when bringing it back to idle.

So I believe I will leave it there and see how it reacts when I go fly next time. I think the main issue was I had the low end too far out of adjustment. Thanks for your advice.

Mike 48

No problem, I've found that all 7 of my 55's, two 30's and two 20's all run right at about 1 1/4 on the L plus or minus a couple of "needle widths". 1/8 turn is a LOT on one of these little engines.

Good luck!!! Glad it is working better!