spark plugs????

[shreker]

I have been pounding my head trying to figure out what sparkplugs i should use on my 1973 mercury outboard thunderbolt 4 cylinder. I have read and read and no one has a straight answer. Can anyone help..... ive heard ac-v40ffm,ngks and gap should be at .030 or 0.40. Anyone please!!!!!!!

 

[Alumarine]

A serial number and horsepower would help.

 

[Faztbullet]

V40FFM are gapless plugs, that motor uses them or NGK BUHW which is gapless also...

 

[shreker]

sorry! 3498334 85hp

 

[shreker]

A serial number and horsepower would help.

3498334 85hp

 

[Chris1956]

Champ L78V for that motor

 

[Faztbullet]

If you use a Champion the correct number is L76V.....................
Plugs you can use are:
AC....V40FFM Hard to find)
NGK....BUHW
Champion ...L76V

 

[shreker]

thanks guys fro the responses.... I went with the buhw ngk's crazy looking tho!