Thank you for your question and the pictures. 310000 Briggs Repair Manual download free more. 2015 Nissan Frontier Service And Repair Manual download free. I am sorry you are having a problem with the tractor. The port on the top of the carburetor is a breather. If fuel is leaking out of the vent, there is a problem with the float or the needle and seat. I recommend removing the float bowl from the bottom of the carburetor. Then remove the float, needle, and the fuel supply line.

Once these are removed, spray carburetor cleaner up through the fuel inlet, where the needle goes. After it is flushed out, check the buoyancy of the float. To do this, drop the float into a glass of water. If it floats, the float is good. Reassemble the carburetor and check the operation.

Note If the fuel line feels soft or is cracked I recommend replacing it from the filter to the carburetor. The ethanol will break down the rubber in the fuel lines and plug the inlet of the carburetor. I hope this is helpful.

Please let me know if you need further assistance. Here is a link to order any parts you need.. If you do not feel confident repairing this problem yourself, then you can have it repaired at your home by a Sears technician. Here is a link for the website:. Thank you for using Manage my life. FREE Standard Shipping on orders of $90 or more Purchase requirement calculated before taxes and shipping charges and after other discounts have been applied and must be made in a single transaction.