g1 yamaha wont stay running

[Wolfin1]

i can take the breather tube off back of carb and cover back of carb with hand and it will start and stay started as long as im blocking the back of carb covering and uncovering fast. as soon as i take my hand off back of carb the motor dyies.please help

[GMB74]

You are basically choking the engine, which means you have too much air or not enough fuel going into the engine. Start by checking the fuel supply- is there enough fresh gas in the tank, clean fuel filter, lines not rotten or pinched shut. If all looks good there, disassemble the carb and clean out the jets and passages. Let us know how you make out, and we can proceed from there.

[Wolfin1]

I have took apart carb and cleaned. Took fuel line off and its spraying out fuel but dont cant tell if it is enough. Golf cart place here says any gas coming out of pump is enough. It probably shoots out about inch and a half from end of line.

[wharris01]

Sounds alot like the crankcase seals are shot. Sucking air around the crank and running too lean. Choking it richens up the mixture.

[GMB74]

I would have to agree. Not uncommon to find bad crank seals on a 30-year old 2-stroke engine.

[slonomo]

Sounds like a rebuild is in order. I just rebuilt my 84 model. It was actually pretty easy. You'll need a steering wheel/harmonic balancer puller and a clutch removal tool. You can find posts on here about both and even how to do it. The seals were the hardest thing to remove for me because I was using screwdrivers, ouch. I was carefull, but the right way is to use a seal puller tool avail at parts stores. Good luck.