in the box just above your top spark plug (four flat head screws hold it in)
Thre is no gap on the plug as it a surface fire plug.
1988
yes but they are a problematic motor
1988-89
The spark plugs on a 1988 model, 70hp Johnson outboard, should be gapped to .030in.
9.9 force
50:1
23 years old made in 1988
The listed dry weight for a 1988 model, 70 hp Mercury outboard is 265 lbs.
The dry weight for a 1988 model, 20 hp Mercury outboard is 105 lbs.
The dry weight of a 1988 model, 70hp Yamaha is 233 lbs.
The 4 stroke Yamaha outboard requires a quality SAE 10W-40 motor oil.