Hi folks, have a Husqvarna yth1542xp with a Kawasaki fh430v engine. 20yo now and the carb was acting up so I went on Amazon and got a replacement that said would fit my engine. The only thing that was "off" was the size of the drain port at the top. The OEM carb had the port shown in the picture I am uploading. But the new carb drain port is half the diameter of this one. The tubing doesn't fit on it. Not sure what to do. All of the carbs I see for this model on every website show this small sized drain port and not the larger one seen on the OEM carb. Any guidance would be appreciated.

Not sure what a drain port is on the TOP of the carb..
 
Is / could this be a vent from the crankcase?
 
If so, you should be able to find some Step down fittings (automotive/auto parts store) to adapt one to the other...
 
If you could post a picture, it'd help..
 
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