.04 inch
where are the spark plugs on a yamaha115 4 stroke motor
The spark plug gap for most Yamaha outboards is around .030 - 0.035in.
.35
you have to make ngk b8hs-10
gap should be 0.9mm (0.035") N.
The recommended spark plug gap (per NGK) is .039"
40
A 50hp Mercury 4-stroke outboard motor typically has two spark plugs. This configuration is common in smaller outboard engines to ensure efficient combustion and performance. Always consult the owner's manual for specific maintenance and specifications related to your motor model.
.030
There are several possible reasons why a Yamaha outboard motor may not start, including issues with the fuel system, spark plugs, battery, or ignition system. It is recommended to check these components and consult a professional mechanic if needed to diagnose and fix the problem.
The 1998 model, Yamaha 250 hp outboard, requires an NGK BR9HS-10 spark plug, gapped to .039 in.
The Yamaha Pro 50 outboard requires an NGK BR8HS-10 plug, gapped to .039in.