Mine is a 2000 model and it has an NGK R BPR7HS10
The spark plug gap for a 2003 Mercury 125hp outboard motor is .040"
A Mercury outboard will run well with a plug gap of .035 - .040 in.
40
What is the correct spark plug gap setting for a Mercury outboard 2003 200 HP EFI
spark plug gap for a 1996 mercury 30 hp outboard motor?
What is the spark plug gap for a 9.9hp mercury outboard motor
Doesn't this engine use a rim fire plug? No gap to set on those.
For a 2005, Mercury 3.3 hp outboard, a NGK BPR6HS.
The correct spark plug gap for the 1982 model, 9.8 hp Mercury outboard is .040 in.
The recommended spark plug for the 1977 model, 7.5 hp Mercury outboard is a Champion L78V, or NGK BUHW-2. Both brands are Perma Gap type plugs, with the Champion being the manufacturer supplied plug back in 1977.
The plug gap for a 9.9hp Mercury outboard, ( all models ), is .035 - .040in.
.035