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Asp 75 wont prime or hold a prime

I have a ASP 75 that's been setting for about 10 years , I put it on my bench test stand tried to get it to prime and hold a prime, it's not pulling up fuel when I put my finger over the carb I replaced the carb O-ring but no luck?

I can blow into the tank vent and prime it the engine will starts and the dies? I see that the fuel hoes has air in it I'm thinking front bearing seal. My fuel in the tank isnew and along my fuel hoses plus I have ran 5 engines with this set up.

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by: Nick

I'd be surprised if air was getting in from the bearing. It must be the carb if you have successfully used the same tank on another engine as my first thought was a leak in the clunk pipe.
Does it fire and run for a while if you put some fuel into the air intake? If it does then its a fuel feed problem. Also have you ever had the engine apart? It might be that the sleeve was replaced in the cylinder the wrong way round. Can you see the intake port looks OK? Clean all the carb parts in clean fuel and you should unscrew the needle about 3 turns and then get fuel going thru. Good luck.

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