How to Sharpen a Lawn Mower Blade

Great information here. I would add, echoing at least one other comment, that mower blade installation should *always* be done with proper torque (typically around 40 ft. lbs). Correct torque is critical because problems can occur if the blade is installed with either too much *or* not enough torque on the installation bolts. Also, some mowers have special concave washers for the blade bolt(s) that need to be installed in the proper direction. Check the manual for both of these.

FYI, a torque wrench allows you to measure the torque (the twisting force) you apply to a bolt so you don't over tighten or under tighten.  They're available at stores (like Sears) that sell automotive tools.
If you HAVE (or can borrow) a torque wrench, by all means use it to tighten bolts to exactly the correct torque listed in your manual. The manual for my mower gives a minimum and maximum torque for my blade bolts so there's some safety margin.

When changing your oil, if you tip your mower on the other side so the drain bolt is facing up, you should have no mess what so ever.

Good video with great info. I'm glad you didn't bore us to death with all the commonsense "safety rules" that the retards need to keep from cutting a foot off. I also liked your tip of using the old oil to coat the deck, take that Greenpeace!

I think greenpeace would approve -it's recycling.

You are the best "how to" guy on youtube!!! 7/5 *

I've used both 80-grit grinding wheels and 60-grit wheel but can't tell any difference in the way the blade cuts. You're not striving for a razor's edge here, like a wood chisel, so there's no need to fuss to get a fine edge. Right off the grinding wheel (or file) is good enough for a lawnmower blade.

Thanks again. Any ideas on how to increase the updraft to really suck the grass before it gets cut to ensure every blade of grass gets the same type of attention?

I use whats called a high lift blade designed for use with a bagger attachment. If you look at it it is bent more and this causes the grass to be sucked up and blown out the discharge further and faster.