Got a DA-50 that hesitates when throttle is advanced quickly. If I bring it back right away it will recover, and stay running.

Which needle do I turn, what direction, and how far ? ? ?

Thank you.

Ed

Low needle for sure. But which way is the question. If it stumbles and smokes...but eventually gets up to RPM it's rich. If it just hesitates with no smoke, it's lean. From your post sounds lean but I'm not there to see and hear it. The way to adjust your low needle is to first set it rich...about 1 1/2. Then keep leaning until it no longer transitions (maybe where you are now). Then just richen it up a tiny bit at a time until you get a very fast transition. Then it's perfect. The key is to find that lean/rich point and adjust it a little richer for the fastest transition possible (acceleration).

" If it just hesitates with no smoke, it's lean. "

Can't really tell if it smokes when it's 50 yds down the runway, but it almost comes to a stop if I don't back off. Then I get the message, turn it around for another take off, and advance it slower, and it's OK ? [&o]

Ed

Stand in front of the stab and just test it in the pitts. I wouldn't fly until it transitions well. I guess I'd just richen it up a little and see if it gets better or worse. If it gets worse you went the wrong way. Try leaning. Don't be afraid to tweak the needles. It's fun !!!

Problem is, I'm dealing with a fully cowled engine, and the cowl must be removed to tweak. But that's my problem, and I'll work it out.

Ed

As modelers most start with either fully exposed glow engines or glow engines fully cowled that have the main tuning needle exposed. That makes engine tuning access easy. Unfortunately there are many fully cowled glow engines where the low needle in the carb has never been touched because it is covered over by the cowl....

A very simple solution to tuning a fully cowled gas engine is to drill a hole or two in the cowl permitting access to the carb needles from the outside. If visual appearances take precidence of correct performance that nice exterior appearance may not last very long. Plane later to hit ground and go splat[X(]

Ed - Post # 6 from Tired Old Man is exactly right. You need to choose to make it adjustable or you will damage either engine or airframe, or both, without question, someday. Form follows function.Make an access hole.

It doesn't take a very big hole and sure beats the hassle of taking the cowl off.