Float and Carb question

Hello, I have a Crafstman LT 1000 917.272660. Briggs and Stratton 31C7070230E1. Gas is leaking into the oil almost as soon as you start the mower up. White smokes starts coming out and gas leaks from the exhaust as well (small amounts). I took the bowl off to see if there was any junk in there and the needle seemed ok. I changed the oil but of course it didn't help for long. Anyways to save time and since the carbs seem cheap enough I was just going to buy a new one. Manufacturer #591731

Here are my questions. Does the float come with the carb if I buy a new one?
Is there anything else that could be causing an issue?

I know there can always be something but typically would replacing the carb and float solve this? I just want to make sure it's worth a shot anyway at fixing the mower. Sorry for the float question but I really don't know much about this stuff. I can replace parts but that's about it. I tried searching for the float question but couldn't find an answer.

Thanks

Yes, the float comes in a new carb. Carb overhaul kit is cheaper than a new carb but if you rather buy a new carb, go for it. The reason why this is happening is because the float needle isn't sealing in it's seat or less likely a float(crack) that's intaking fuel.

Change your fuel line while you are at it. Old hoses tend to leach out little crumbs of rubber that will cause your problem to occur again!

A little more on why. The float that is punctured takes on gas and loses bouyancy (sp?) so it will not close the needle on the seat and stop gas from entering the carb. I have never worked on a lawnmower carb, but there may also be a "stroke" factor. This is how low the float is allowed to drop into the float chamber when demand has emptied it. The other end of the stroke was how high the float is allowed before the inlet needle is seated (shut off). The stroke used to be controlled by a metal tang that was bent . Little cardboard gauges were used to get the dimensions which were called out in the workshop manual or float kit.

Thanks everyone i appreciate it. probably a good idea on the fuel lines. i was thinking that as well and it's cheap enough. i would rebuild normally but just to save time and maybe more headache ill prob just replace the carb.