1981 ATC 110 Carb question

[retiredmxer]

I just picked up this 110 along with the purchase of my new house. I saw it in the shed when looking at the house and included it as part of my contract offer :)

I've got it running, but I have to leave the choke on so it doesn't bog. Air leak somewhere I suspect. I took the carb apart before starting it just to give it a good clean and now I'm looking at it more closely and am wondering what this opening is.
Also, I have a gas leak behind the petcock, so I've ordered the o-ring, filter and new screws as well. I guess that gas leak could be the air leak, but it seems small.

Any info on what that opening on the carb pic is would be great. I didn't see anything in the service manual.

Thanks

blake

http://i566.photobucket.com/albums/ss107/retiredmxer/th_81110carb.jpg (http://s566.photobucket.com/albums/ss107/retiredmxer/?action=view&current=81110carb.jpg)

[SYKO]

thats just a carb vent line, there is just suposed to be a rubber line connected that hanges below the engine thats all, as far as air leak is concerned take the intake and carb off and use some rtv sealent between the engine and intake and intake and carb and let it dry good

[Lukeatc185]

yep thats just a vent, there should be a small clip inbetween the flywheel area and above the chain sproket a small rubber hose clips there and attaches to that outlet on the carb.