evolution 40 hesitation
 

Hi all. away from home for work. Last weekend I took my trainer to the field to fly (easy2) The Evo engine will slightly hesistate when going from idle to full throttle. it flies fine, but I worry about the engine dying. I've tried adjusting the high end mix, but no real difference. Only seems to do it after idling on the table for a while. Once I'm at full throttle and then go back to idle and then full throttle again, it's fine, not hesitation. Should I worry or just fly/!
TIA

RE: evolution 40 hesitation
 

the low end is to rich by the description try leaning the low speed just a bit

RE: evolution 40 hesitation
 

Uh-oh. The infamous Evo mid range hesitation. Drove me nuts. Never really figured it out. That was on a 100 NX engine.

CGr.

RE: evolution 40 hesitation
 

its normal to hesistate slightly after idling for a long period of time, its caused by the engine "loading up"
the fuel flows into the carb and down to the bottom of the crankcase, where it waits for the piston to move down and force the fuel up through the ports in the sleeve, if the engine is running at a lower rpm it isnt burning as much fuel, hence the extra will "load up" in the bottom of the crankcase, when you add throttle your feeding more air, more fuel from the tank, and pulling the fuel sitting in the bottom of the crankcase in at once hence it bogs a bit, then when you let off and punch the throttle to max again its fine.

Lean the low speed about 1/16th of a turn and go fly.;)

RE: evolution 40 hesitation
 

Ditto, BUT...

Remember where the Low End needle was to begin with (maybe you can scratch the area around it as a marker). If it helps, but still hesitates, turn it in another 1/16 turn. Keep doing this until it's right. There is also a slight chance that you may need to open it instead of closing it.

RE: evolution 40 hesitation
 

I agree whole heartedly with what everyone has said

But would like to add - Move the low speed needle in 1/16 turn increments and try the engine acceleration after idling some before moving the needle again.

Also the Evolution glow engines have too much cooling fins and need a "Hot glow plug" like the OS #3 or Enya #3 to throttle well

The needle stops may need to be moved or adjusted to get the needle in the correct position

RE: evolution 40 hesitation
 

Ugh, the infamous 100NX. I have mine in a clear box on a shelf to remind me not to buy one again.


However he says he has the 40.

I've found the smaller engines to work very well, once you eliminate the useless and problematic limiters.

It does sound like he is running the low end a bit rich, and this may be the fault of the limiter or the "walking needles" which the Evolutions are so prone to do.

RE: evolution 40 hesitation
 

Oddly enough, I had both plus the 61 I believe. They all gave me some sort of problem. Some like them and have no problems with them. Some have lots of problems.. I am one. And that 100NX was an extreme pain in the butt. I took it to the LHS on consignment and I thing it's still there.. after about three years... or he junked it, not sure what.

CGr.

RE: evolution 40 hesitation
 

yep sounds like the low end is a tad fat lean it ever so slightly

RE: evolution 40 hesitation
 

Thanks all, was actually thinking about messing with the low mix screw. Will give a whirl next time. I brought m Park Zone 3D with me for this trip. I'm in Quantico. Va. There is nothing but trees trees and more trees. Fredericksburg is about 15 miles down I 95. I emailed a club called areomasters there, to see if they will let me fly as a guest while I'm here. Otherwise I'll keep looking for a big open field or parking lot.

RE: evolution 40 hesitation
 

about the glowplugs, i ran a OS #8 with no problems, and Mccoy MC59 long hots too.

RE: evolution 40 hesitation
 

The Aeromaster's are a great group of guys they are actually in Stafford county just north of Fredericksburg...tell 'em Smitty sent ya