Earthstar Forums

My Earthstar Soaring Gull still has a problem in that after an hour plus of flying ,upon entering the pattern and easing back on the rpm it will suddenly lost power .Usually when this happens it will repeat itself a few more times at erratic intervals.It smoothed out when I eased throttle forward and simultaneously hit the electric pump.At that point my goal was to just get safely on the runway.    Trouble shooting so far includes checking all fuel line connections (no worm hose clamps just double safety wired ), tightening up throttle lever next to seat, changing spark plugs, fuel filters are clean ,using ethanol free 93 octane gas.   EGT and CHT temps are in the green.I usually fly with rpm in the 4,950 to 5,250 range. So it wasn't a case of going from wide open to fast idle.   Having done all That ,could it be a case of carb problem ?  It shakes alot at low rpm but is smooth from 2,800 to full throttle.BTW the old plugs were oily black. I had been gently cleaning them with a small bronze brush on two occasions.    I think the problem is narrowing down.,because previously when checking plugs to see if they needed replacing after many hours of running ,they were gray.  Gap is now .65mm      What should be done next ?          Thanks, Carl

Oily black plugs is not a good sign.

Skot Weidemann

Hi Carl
I don't clean these plugs. If they are oily black it looks like one or both of your carbs are to rich at idle!
Or dirty air cleaners. Wash them by soaking them in soapy water for an hr than rinse them out from the inside out and let them dry and re treat them with the K&N air filter oil.

It is possible that the idle jet has gotten clogged, it's very small and clogs first.

Hope this helps
Happy Flying
Mark

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Mark: This HKS does not have 2 separate exposed air filters. Incoming comes through a scat tube into an air box then splits to the Carbs. So is there a filter that is in each side covered over by the air box ?
idle jets being clogged would explain the rapid plug fouling because the old plugs were all
light gray , now suddenly they keep fouling.
Otherwise , this plane performs like a champ...which as you know is a lot better than a Cub
Merry Christmas.
Thanks ,Carl

Hi Carl
There are 2 air filters in the air box.
Happy Flying
Mark

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