Frequently Asked Questions Answered by our Experts

1.0 Lawn Mower Blade removal

Most blades are held by a single bolt with a beveled washer that keeps tension.

Remove the spark plug wire so the mower can't start.

Use a 6-pt socket with a fairly long ratchet or breaker bar to remove the bolt. This will prevent you from rounding the corners of the attaching bolt.

If the blade has been removed regularly, holding the blade with a leather gloved hand and using the rachet with the other, works well. If, not, you will have to wedge something like a block of wood between the blade and the deck to prevent the engine from turning while unloosening the bolt.

Clean up the threads using a wire brush and apply anti-seize compound on the threads works wonders for easier removal the next time.

Take the blades off to sharpen and balance at least yearly

[b]2. Preventative Maintenance

Most engine problems are carb related. One thing to check is to remove the carb bowl and see if you see any moisture or debris. The moisture will look like little beads inside the fuel. If you have fuel contamination, clean the ENTIRE fuel system. This includes the fuel tank, fuel lines, and carb. Also, replace the fuel filter and add fresh fuel.

Rewinding the string on a trimmer. Most trimmers hold about fifteen to eighteen feet of trimmer line. Remove the trimmer head, divide the line and leave one end about four to six inches longer. Begin winding the line in the direction of the arrow on the head being sure to keep the line going around straight and taut. Hook the two ends on the head, and guide the line through the holes. Tighten the head, and go to trimming.

When the engine is backfiring and popping, it is usually a sheared flywheel key, or valves. And yes just because you have spark, does NOT mean that the flywheel key is Okay. The key can be sheared and you can have spark, but NOT at the Correct time.

What is needed for all engines, fuel, air, compression, and spark.

Weak battery? Maybe not. If your engine turns a little and stops, then goes on to try and start. Or if it turns a little and then stops and doesn't move. Your VALVES may need to be adjusted. Now some batterys do go bad of course, but a lot of shops will sell someone a battery when that is not the problem, but the newer battery may turn the engine over better and result in the engine starting. Valve adjustment on a twin cylinder takes about 30 to 45 minutes to remove the hood, and set both cylinder's valves.

Pull rope replacement.
DO NOT DISASSEMBLE THE HOUSING AND PULLEY, THE SPRING WILL COME OUT.
Remove the blower housing. (top of engine)
remove all the old excessive rope.
for mowers with the rope through an eyelet on the handlebars (most will be this way now),
Take about seven to seven and one half feet of rope.
rewind the spring. To test, wind about one and a half turns and let go. If the pulley winds back by itself, you are winding the correct way.
Tie a knot in one end near the end, burn the end and make it stick back to itself while still hot and let it "bond" to itself.
wind the spring again all the way and carefully allow it to back off about one to one and one half turns.
insert the rope through the pulley and out of the blower housing.
tie a knot about one and a half foot from the other end.
let go of the rope, it should retract back into the pulley.
If rope don't go back in, you don't have it right, start over.
If you done the spin back test, you will have it right though.
put the blower housing back onto the engine.
depress the bail handle if equipped.
pull the rope up and through the eyelet.
Tie another knot around eyelet.
Put handle back on.
Untie from eyelet.

Preventative Maintenence - Lawn Mower Blade Sharpening V 1.0

A sharp blade makes a nice lawn. Sharpening the blade once per season seems to work well.

Now that you got the blade off, what now? First take a look at it and see if it’s symmetric. If the blade is bent or it has some major chunks out of it, replace it.

When you’re done, you need to end up with a blade that’s both sharp and balanced. Let’s look at balancing first.

Checking Blade Balance

Materials Required

A Vise and an object with a cylindrical part like a screwdriver –or-
A huge nail and a board. By huge nail, I mean the ones you buy one at a time and are about 8” or longer.

Arrange the round object such that it’s level and when the blade is perpendicular to it, the round object can support the blade. Place the middle of the blade onto the nail and the blade should balance around the round object. Eyeballing works fairly well. 100% perfection isn’t required.

Sharpening Methods

There is the old tried and true oil honing method where a sharpening stone and honing oil are used to put a fine edge on knives. We don’t have to get this picky.

There is the bench grinder with a fine stone. You can substitute an angle grinder and a vise if you like. This method tends to take off too much material and makes the blade hot. It will work, but it tends to turn the blade blue, which isn’t good because the blade gets hardened and can shatter. Usually with the bench grinder method, water to cool the item isn’t too far away. You may have to use this method if the edge is extremely dull.

My favorite method is to use the Lawn Mower and Gardening Tool sharpening attachment #675 which uses an Aluminum oxide stone #932 for your Dremel tool. The blade thickness can’t be more than 0.160”, or about 5/32 of an inch to use the jig.

Mulching mower blades can be quite difficult to sharpen because the cutting edges are not straight, but the stone without the attachment works well. I haven’t tried it with honing oil yet. Besides, you can get a second one for all your kitchen knives.

You can always give up and bring the blade to your favorite lawn mower shop.

Personal Protection Equipment
Goggles when sharpening the blade to protect your eyes against stone shattering

Recommended, but not essential, use gloves to protect your hand from the sharp edges on the blade.

Put a nice edge on it and check the blade balance. If it tips, remove more material from the opposite side. If you do it at least yearly, it doesn’t take very long and your lawn will be much happier.

Comments via PM welcomed.