I have a 63FZ, new from the box. Run twice with 90% 209/20 and the remained 10% composed of Omega in the last two days. Engine starts easy, runs slow but very nice but will only accelerate to abou 8,600 RPM - half throttle. It has a 12 X 8 prop on it. Gets pretty hot while running for a while. Touched the intake manifold and it was very hot (I would expect it be sort of cool as on other four strokes). First run HSN set at 3 turns out, tried 2.5 turns but still same problem of accelerating above mid range. I observe a lot of spit back going on in the carb throat. I observe that the card barrel/plate is only open about 15% to 20%. Runs steady at that speed. Ran three times very rich, then today second major run, ran for 11 minutes and stopped.

Running richer, e.g. 3 turns out, still will not run over 8,600.

Appears to me to be running lean, but three turns out on the HSN ought to be plenty but . . . .

What gives?

Chip

No response.   I am suspecting an airleak around the back of the engine.  I had to wipe up some dirty oil at the seam between the block and the fuel assembly.   Lean operations seem to indicate an air leak, so I will remove the engine and retorque all the bolts.  That may do the trick.  I jsut hate to remove engines to do this, especially since the engine  is brand new.  Any rate the little Castor from the Omega will probably do its job and protect the engine.

Here I am ansering my own mail.  Duh!

Cheers,

Chip

Hello, anybody supporting YS?  Gone flying?

I don't have a 63 so I can't advise on the number of turns on your HS needle. From what you've said, it sounds lean to me also. Here's a link to a site on tuning the YS engines. http://www.geistware.com/rcmodeling/...ys_engines.htm
Paul

Another good page on YS setup with more current info:

http://www.patternflyer.com/troy/?page_id=13

Thanks reklaus,

I guess YS does not care or has no answer.  I guess that is about the same, isn't it.  So much of RCUniverse forums.

Cheers,

Chip

This forum is no longer monitored by YS. It is just a bunch of us YS owners who do our best to help based on our own experiences. Right away you have an attitude even though folks tried to help you.

The best thing for you to do is to call Richard at yspartsandservice.com. Don't send an email, call him.

I have used the method posted on the geistware site for a lot of years and it has yeilded better results for me but YMMV. That being said, what plug and fuel are you running and where is your regulator set? Flush? Above? Below?

As noted there is no YS rep monitoring these threads, just a bunch of us who love the engines and try to help out as our time allows. If you need an immediate response you can always call YS Parts and Service.

Icontinue to get air bubbles in the line going to the carb. The line is supposed to go solid with fuel at high speed but no luck. When left at idle the line will go completely dry and the engine dies.By the way it is a 63 engine. Any suggestions.

Just a couple quick questions:
1) have you checked all teh fuel lines in the system including those in the tank for nicks?
2) have you had the regulator housing apart by any chance?

FWIW...Some basics...Is the fuel/system generating & HOLDING (after a static hour or more) pressure?...If not , this HAS to be diagnosed & corrected....
Ed