110FZ
 

Dave:

Question on the regulator. I've got a pre 2006 YS110FZ with about 200 flights on the engine. I had it in the shop about 60 flights ago for a crash test. Everything was OK. Only the gaskets needed replacing.

I've finally got it dialed in with the regulator screw 2-3 mm above the casing. Is there a problem with this? I was told by someone at my club that the regulator should be no higher than flush with the casing.

There's a fair amount of smoke, so its definitly running rich. Power seems good. My problem has been the engine quitting on quick transition from WOT to low idle when I chop the throttle, and it kept dying on low speed idle during landing final. Got that solved first by richening the regulator, and then richening the LS idle valve. (I noticed that when I leaned the regulator too far, the engine idle would "pulse").

I noticed that the engine did not idle stable at low speed...it would hit 2,000 then bounce up to 2,400, then back to 2,100, then up to 2,500, etc.

At the current settings, none of these problems exist.

I guess I could lean the regulator a turn or so, then attempt to address the WOT to LS idle via adjusting the LS idle.

Sorry if this is confusing. I wish I understood the pumped system better.

Comments?

Thanks.

Steve

RE: 110FZ
 

First of all the regulator is meant to be adjusted. Where it finally ends up is of NO consequence as long as the engine runs properly. I don't care if it's above or below the casting edge as long as it functions correctly.

Go to www.ysperformance.com and follow the running instructions. It will give you some clue as to how to properly set one of these things up.

By the way, the YS DOES NOT use a pump, except in the case of the DZ versions. All the other YS engine use a high pressure regulator system. The regulator adjustment screw DOES NOT change the pressure, it only allows a regulated amount of fuel through the engine based on throttle position.

RE: 110FZ
 

Thanks so much for the quick response and the info on the regulator system operation. That helps clear up some of my confustion, for sure.


I'll leave everything exactly as it is.

Best,

Steve