Originally Posted by darryl gesner
There's generally no need to disconnect the spark plug before changing the blades on a zero turn mower because the blades are not directly connected to the engine the way they are on something like a 21 inch push mower. Therefore turning the blades does not turn over the engine. If you want to be ultra safe I suppose you could disconnect the plug wires. And as far as disconnecting the plug wire on a small mower...make sure that it is well away from the plug when you do disconnect it. They tend to return back to their postion and could touch or be close enough to the plug to cause it to fire.
VERY good point Darryl.
This might seem ridiculous and just common sense, but wearing gloves is always a good idea. I was changing blades with some resharpened ones, I just barely bumped my hand on the cutting edge and it was noticeable