Tried my fitrst YS engine today without succes.
It runs for 20-30 seconds right. Then pressure in the tank builds up and it starts running rich and stops.
At that time fuel is foamning and streaming out of the carb.
Turning the needles does not seem to help. The pump screw is 3 turns open and should not be touched according to the instructions.
What am I doing wrong?

It looks like this post:
http://www.rcuniverse.com/forum/YS63...1994419/tm.htm

But the lines are correct according to the instruction leaflet (fuel-line at the exhaust side)

Some debris may be holding the regulator plunger from sealing. Take the regulator apart and clean it. Refer to the instructions at www.ysperformance.com.

The regulator screw should be set flush with the top of the regulator body as a starting point.

Dave, the engine is new. Opened it and found nothing that should not be there, as expected.
Can you tell me how the sealing works?
Noticed that turning the screw in increases the spring tension.

As we have discussed here many times before, the regulator controls the transition between idle and full throttle. The starting point for the regulator screw is with the top of the screw flush with the top of the regulator body.
From that point you will either lean or richen the transition by rotating the screw either clockwise to lean and vice versa.
If you are losing a large amount of fuel into the carb with the tank pressured up, the plunger is not sealing, either due to debris, damage or improper assembly.

Did you completely dis-assemble the regulator and did you re-install it on the engine correctly? the bump on the casting faces to the front of the engine.

The engine is new, and I could not find debris of the manufacturing process.

Later I found out that the screw can be turned out totally and that it can be removed.
A spring and a plunger and a silicon small thing was in. There was no debris there too.

I did find a comment in this group that with the given symptoms the regulator is turned a 180 degrees, so I tried with the bump backwards.
Now the leaking stops, but engine only fires a few revolutins each time. I assume no fuel enters the engine at all. This was obviously not the solution.

Did you buy the engine from the USA. If so, I would recommend that you send it to:

YS Service
1295 Industrial Court
Gardnerville, NV 89410

The engine is bought from a local dealer that imported (grey?) a few engines.
I expect that I have to solve the problem by myself.

If you can't figure it out yourself, send it here. We can fix it.

Dave, when I try to blow (by mouth) through the fuel delivery line, there is not much resistance when the screw is flush.
When i turn the screw in, the fuel line gets closed when the regulator screw is turned 1/2 to 1 mm in.
At this setting when i apply some suction at the blue fuelline (the one that is between the regulator and the carb) the valve opens and air is admitted.
Based on these facts is perhaps for me the starting point for the regulator screw 1/2 to 1 mm turned in? Or doesn't it make sense what I'm doing here?

Regards,
Hans


Hans Meij / Modelvliegen

Found this source of info:
http://home.comcast.net/~mark.fuess/ys110.htm
Perhaps the idle was just to high. Next weekend I'll know, hopefully

Regards,
Hans


Hans Meij / Modelvliegen

OK with me, let me know how it goes.

Dave, tried last weekend again and was not to successful.
Lowered the idle setting and this prevents to much pressure built up and stops the leaking, as suggested by Mark B. Fuess in link.
It still leaks when engine is stopped after running at a higher rpm.

It seems to run wel for a second or ten. As with the previous attempts it starts to run bad after that amount of time.
It is throwing props, destroyed the alu spinner and the prop. It is detonating in transition, but also emits lots of smoke during transition as if it is running rich. Turned the regulator more out then flush with the housing to richen up the midrange but stil is detonating.

For the time being i'm giving up with this engine (brand)
Thanks for your help, time and patience.

I believe all your problems are related to improper fuel and improper adjustment. Please don't comdemn the engine without first sending it to us for a look.