Snapper Lawn Mower Blade Bolt Size . Here’s what most manufacturers recommend: Carefully lower the front of the mower until the front wheels are on the ground. Snapper Shear Bolt 7091550YP Power Mower Sales from powermowersales.com Remove the filler cap from the fuel tank. A socket wrench that isn’t the right size will not move your bolt and is likely to get stuck. Click to see full answer likewise, people ask, what size bolt is on a lawn mower blade?