problem with ys .50

[mexitom]

a friend of mine had a new ys.50 st engine.
the problem is the nitro is going out throw the hole of the carburator...what happen with is engine...sorry with my english ...i'am fench.
i a have a ys too and it work very well..
thank u

thomas

[DavidH]

When it is spitting fuel out of the carb. The mixture is usually too rich. Another thing that can cause this problem. Is if the carb opening is inside the fan shroud, the air being forced by it from the fan can vaccum the fuel out of the carb and onto the motor.

David

[archiebald]

a friend of mine had a new ys.50 st engine.
the problem is the nitro is going out throw the hole of the carburator...what happen with is engine...sorry with my english ...i'am fench.
i a have a ys too and it work very well..
thank u

thomas

Are you running the same muffler as your friend? When I first changed to a YS50ST I was still using an old muffler with too much back pressure. I had lots of spit back from the carburettor and very low power.

Changed the muffler to a Hatori #522 and the power increased and the carb remained dry.

But if you are trying to explain leakage from the carb, then it could be a faulty or sticking regulator.