US 12,345,197 B1
Marine engines and methods of making marine engines having cylinder liners
Daniel P. Hoffman, Fond du Lac, WI (US)
Assigned to Brunswick Corporation, Mettawa, IL (US)
Filed by Brunswick Corporation, Mettawa, IL (US)
Filed on Apr. 17, 2023, as Appl. No. 18/301,727.
Int. Cl. F02B 61/04 (2006.01); F02F 1/00 (2006.01); F02F 1/16 (2006.01)
CPC F02B 61/045 (2013.01) [F02F 1/004 (2013.01); F02F 1/16 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A marine engine comprising:
a cylinder block that defines a cylinder bore; and
a liner that is cast in place in the cylinder bore, the liner being axially elongated and providing a piston running surface,
wherein the liner comprises a first outer diameter surface portion defined by one or more grooves,
wherein along the first outer diameter surface portion, the cylinder block has an interior surface with one or more protrusions, said one or more protrusions being formed by casting the liner in place in the cylinder bore such that said one or more protrusions are interdigitated with said one or more grooves and thus together provide a mating interface that axially constrains back and forth movement of the liner with respect to the interior surface, and
wherein the liner comprises a second outer diameter surface portion that is smoother than the first outer diameter surface portion and is axially unconstrained with respect to the interior surface under operating conditions of the marine engine, and wherein the second outer diameter surface portion abuts the cylinder block along a length of the liner, thereby inhibiting fluid flow between the second outer diameter surface portion and the cylinder bore.