I was wondering if either Dave or any of you other YS gurus could shed some light on a problem I am experiencing. My 63FZ is having a problem with quitting at high throttle. I weird thing is it does not happen with the glow ignitor attached. With the glow ignitor attached the engine runs perfect. Upon removing the glow ignitor at idle there is a noticable loss in rpm. When the engine starts to choke down at 3/4 to full throttle all I have to do is reattach the ignitor and the engine clears up. This sounds like the glow plug is not good but it is a brand new OS F. The engine is mounted inverted in an flip3d. I run it on powermaster 20/20 with an 13x4W APC prop.

I was also wondering if a conversion kit is going to be available to move the regulator to the new position on the YS 63S. This would help us who have problems with the engine on the hot, humid days like here is on the Gulf Coast. This would be an nice option to be made available.

Thanks

Christopher Belt

I would also like to add that I went through all the usual items when checking the engine out. I checked the check valve, tappet clearence is at .003, Diaphram is good with not stretching or holes. Put in new plunger assembly and new spring. The original plunger assembly had a raised notch in the middle of the disk that was sharp. The new one is perfectly smooth, so was the original assembly defective? I also check to see if there was any debris in the regulator housing plugging the holes and check the fuel filter for blockage.

The engine is telling you that it's running too cold. Try screwing the HS needle in a bit more, my hunch is that you're trying to run it too rich. A couple of hundred rich of the peak is all you need.

There are more differences between the 63FZ and the 63S than the regulator location and we do not plan to refit the FZ.

Thanks for the quick reply. I will try this out tommorrow. I was thinking it might be the plug because it started happening when I installed it. When checking it on the glow heater it has all the coils lit but the last turn on the coil. The other plug did not make it die all of a sudden like this it just gave me midrange problems. I might try some fresh fuel too.

You can also pull the element up out of the plug a little with a pin. That will make it run hotter.

I was pretty successful is adjusting the engine to run decently today. Leaning the high speed needle, regulator a 1/4, and some adjusting on the low speed needle helped get it running better. It tends to gain a couple hundred rpm after the engine returns to idle from max throttle. Does this mean that it need to have to low speed leaned or the regulator. It will go from 2400 to about 2700 rpm in a few seconds. Otherwise it seems to be running correctly with great power. 11200 rich for flight on a 13x4W APC. This is on YS 20/20.

Thanks
Sport10

The rpm increase indicates that the idle is still too lean. Turn the idle screw 1/2 turn clockwise.