Carburetor Adjustments - Mercury 10/15 Sea Pro/Marathon - 6/8/9.9/10/15 HP User Manual

2. Remove the spark plugs to inspect. Replace spark plug if electrode is
worn or the insulator is rough, cracked, broken, blistered or fouled.
3. Set the spark plug gap to specification.
Spark Plug Gap
NGK BPZ8H-N-10
NGK BPZ8HS-15
4. Before installing spark plugs, clean off any dirt on the spark plug seats.
Install plugs finger tight, and then tighten 1/4 turn or torque to
specifications.
Description
Spark plug

Carburetor Adjustments

SLOW SPEED MIXTURE ADJUSTMENT
1. Before starting engine, turn the slow speed mixture screw in until it is
lightly seated then back it out 1-1/2 turns.
2. With boat tied securely to dock, start engine and allow it to warm up.
MAINTENANCE
1.0 mm (0.040 in.)
1.5 mm (0.060 in.)
75
ob00423
ob00424
Nm lb. in.
27
ob01424
lb. ft.
20