Ariens 1540 Mower, Lawn and Garden Tractor

Briggs 15hp 28P777-0644 or 28n777

This unit has an electric cluth and a fuel pump. This engine normally has an angle bracket on the oil filter that makes it point toward the spark plug end of the engine. If an engine with an oil filter that comes straight out of the block with no angle bracket on it, it will fit in your tractor and the 31M977-0111 engine should work for you. If you do not have room then you could use an engine without an oil filter. You will have to use your fuel pump and purchase a new dip stick tube as this engine pulls its vacuum from the dip stick tube instead of the side of the block like your engine. Briggs part number 697085.