Re: Head Gasket Rapair on 1972 Johnson 9.5
Run a tap through all bolt holes. It was wisely recommended to me to use new bolts, but up to you of course. No sealant on gasket, but a little gasket sealant on the bolts to keep them from seizing up over time. Start lightly tightening on the center bolts and work your way around in a circle, tightening the bolts farther and farther from the center. Work up to the recommended torque, don't just tighten each bolt to spec. Your manual will no doubt outline this for you. Make sure the gasket is facing the right direction. You might want to check your head for straightness with a straight edge. If it's even slightly warped, put it on a piece of glass with some 400grit sandpaper on it and rub the head on it with a figure 8 pattern to flatten it out. You may even have to start with heavier grit if it's warped bad enough. You MUST use a torque wrench and torque it to specs.
JBJ