EF

I was given an Enya 60X engine that I was told was only bench run but never flown.
It’s very clean and looks brand new.
Smooth turning with good compression.

It starts immediately when primed but won’t continue.
I tried choking it with my finger and noticed it’ll only draw fuel when the throttle is 80-100% open but at lower throttle you only hear the hissing of air entering through the air bleed hole but it won’t draw any fuel.
The air bleed screw is set so that it closes half the hole, probably set that way since it was assembled.

What can be wrong? Why won’t it draw fuel?

jaka54

Hi!
Well...R/C carbs are rather simple. I would remove the high speed needle and blow through the nozzle to see if the there is any dirt inside. Or take my electric fuel pump hose and see if any fuel can go through.

1QwkSport2.5r

Clean out the metering slots in the carb barrel. Most Enya airbleed carbs have a metered barrel; the airbleed is ONLY a trim adjustment.

EF

Thanks, I now seem to be on the right track.
Took the carb completely apart, cleaned it and then assembled it back together.
Also closed the air bleed screw further in than before and now the engine draws fuel very well even at low throttle.
I’m sure it’ll now be OK but will only get to bench run it in the weekend.
Will report the results for the benefit of anyone else who may have this problem in the future.

1QwkSport2.5r

If you still have issues with fuel mixture at throttle settings below 1/2, remove the barrel from the carb again and use a NEW Xacto blade and get every speck of crud out of those metering grooves. There will be a groove on either side of the feed hole. This must be spotlessly clean. Also, if using muffler pressure, expect to have the airbleed trim a little more open. Stick to starting half way closed or a little more closed from 1/2 and work from there. It’s always ALWAYS better to start rich and work leaner.

I have a 60XF IV Heli carb that I was given - I tried using it on my ST .90, but the midrange was so sloppy rich, no adjustment could clear it up. One instance where a Heli carb isn’t suitable for fixed wing/prop engines.

EF

I bench tested the engine today, worked flawlessly.

Started immediately on very low throttle and ran just perfect with a very stable and very low idle and instant transition to full power.

Thanks for the advice!