Mercury Mariner Outboard 225 3 Litre Service Manual 1994, Page 204Get this manual
design will fit as (replacement) cylinder assembly completeDesign will NOT fit cylinder originally using Design tilt rod assemblyMemory Pistons for Design and differ also and must be used only on the cylinder the piston was removed from3Remove washer, check valve assemblies, and pistonNOTE: Check valve held in by roll pin can be cleaned but not removedRemove allen plug IMPORTANT: Remove plug from same side as holes In shaft