Hi everyone

I am a newbie and looking for some help with the GS racing 1/8 truggy engine ( it is for the storm unlimited)
The problem is first the one way bearing for the pull start got damaged and I could not use the pull start anymore, had to dismantle everything to check.
Now I am using a OFNA starter box to start the engine. The Engine runs only till the starter box is in contact with the fly wheel and stalls after it is removed.
I am not sure what the problem is. And I also have not fixed the one way bearing back into the engine.

Could it be the fuel? My fuel was not used for about 6 months and it was mixed locally.

Some please give me an insight into this.