Mercury Mariner 4, 5, and 6HP 4-Stroke Factory Service Manual, Page 23Get this manual
MAINTENANCE
Protecting Internal Engine Components
NOTE: Before performing Steps and 2, make sure the fuel system has been prepared for storage1Change the engine oil2Place the outboard in water or connect flushing attachment for circulating cooling waterStart the engine and let it run in neutral to warm up3With engine running at fast idle, stop the fuel flow by disconnecting the remote fuel lineWhen engine begins to stall, quickly spray Quicksilver Storage Seal into carburetor until engine stops from lack of fuel4Remove the spark plugs and inject five second spray of Quicksilver Storage Seal around the inside of each cylinder5Rotate the flywheel manually several times to distribute the storage seal in the cylindersReinstall spark plugs