Abstract: An object of the present invention is to provide a float assembly that can prevent the floats from flipping. The present invention provides a float assembly including a plurality of floats connected together comprising: a filled float having a hollow portion, wherein the hollow portion has a part filled with a filler, and the filled float is arranged at a position facing an assembly periphery surrounding the float assembly.

Abstract: An object is to provide an engine in which the exhaust manifolds capable of switching a dynamic pressure supercharging method and a static pressure supercharging method can be easily changed to the exhaust manifolds only of the dynamic pressure supercharging method or only of the static pressure supercharging method without replacing exhaust manifolds themselves. In an engine in which a plurality of independent exhaust manifolds is respectively connected to a supercharger, end parts of the exhaust manifolds are coupled to each other by one or more coupling pipes, an on/off valve that brings the exhaust manifolds into an independent state is provided each of in the coupling pipes, and the coupling pipe is configured such that a part including the on/off valve or the on/off valve is detachable from the exhaust manifolds.