Spark PLug Gap

[jeff6898]

1979 85hp 85999R

All the ma

1979 85hp 85999R

All the manuals say to gap plugs at .030 SOmewhere I read that .040 is better. Can someone tell me the correct spark plug gap

 

[joereeves]

"Champion QL77JC4 plugs. The o

"Champion QL77JC4 plugs. The original gap, back as far as 1973 or so was .040 . That recommended gap was changed to .030 at some point around 1991, somewhere in that area, supposedly to make the plugs last longer.

Some engines run better on one gap or the other. Try both settings and compare engine performance. If no difference, use the .030 ."