Hi.
I have a Ys 63 that ran outstanding last season. After sitting on the shelf for a couple of month I fired it up for the first time a couple of weeks ago.
Now the engine is hard to start, I have to choke it allot and after a couple of restarts (10-15 or so) I can finally get the revs up without it quitting (yes I let it run on low rpm ad let It warm up first). I have to choke it all the time when cold, it seems that it can’t get enough fuel.
After this it runs very well and is very easy to restart. It seems that it’s running very lean when cold.
I have now mounted it on a test stand an have fiddled with it allot, so i doubt it is a tuning error. I have checked the carb and regulator for debris.
Fuel is 20/20, os F and 13x6

What should be my next move?

//
Henrik

The first thing to do is replace the diaphragm. They will get stiff from sitting for a long period.

ok, thanks for the fast reply.
I will let you know how it goes.

OK, thank you.

It sure was the diaphragm!! thank you.

Great!

Good Flying to you!