A soft key allows the flywheel to move on the crankshaft when your mower blade hits a tree root, an old stump, a large dried clod of dirt, etc. If the mower blade is loose, that will cause enough shock to shear the flywheel key, too.

What is the purpose of the flywheel key?

A soft key allows the flywheel to move on the crankshaft when your mower blade hits a tree root, an old stump, a large dried clod of dirt, etc. If the mower blade is loose, that will cause enough shock to shear the flywheel key, too.

Do riding mowers have flywheel keys?

This step-by-step riding mower repair guide explains how to replace the flywheel key on a riding lawn mower or lawn tractor. … To protect expensive engine components from damage, the flywheel key shears off if the mower blade hits an object hard enough to make the flywheel slip out of alignment with the crankshaft.

What size is a Briggs and Stratton flywheel key?

Q: which are the dimensions for the flywheel key? A: The keys are rectangular in shape 1/8 X 3/16 X 5/8 They are made of aluminum.

How do I know if my flywheel is bad on my lawn mower?

If the mower blade hits an object with enough force to knock the flywheel out of alignment, the flywheel key breaks, protecting expensive parts such as the crankshaft from damage. If the flywheel key shears slightly, the engine runs rough or misfires. If the key breaks, the lawn mower stops running and won’t start.

What are the signs of a bad flywheel?

• Slipping Gears.
• Cannot Change Gears.
• Burning Odor.
• Vibrations of the Clutch (Clutch Chatter)
• Unable to Start, or Inconsistent Starts.
• Engine Stalling.
• Engine Vibrations with Clutch Engaged.

How much does it cost to replace the flywheel?

We mentioned how flywheel replacement is a hard task as it’s hard for the mechanic to take the flywheel out and replace it. This takes more time and effort so the pay is high. On average, flywheel replacement cost is anywhere between $600 to $1,100.

How many magnets does a lawn mower flywheel have?

There is only one magnet in the flywheel. The other piece of steel is a counterbalance and may have only picked up some residual magnetism. If you’ve got strong magnetism in the one piece, your flywheel is good. It’s possible that your ignition coil is bad.

How is the flywheel connected to the crankshaft?

Flywheel is just a metallic disc which stores rotational kinetic energy form crankshaft. It is connected with help of bolts to the crankshaft.

What is a flywheel puller?

Flywheel pullers are essential engine service tools and they are used in a lot of different jobs. … Most pullers are simple tools, usually consisting of an outer body that attaches to the flywheel and a lead screw to push on the crankshaft. Some pullers are just a hardened bolt that threads into the flywheel.

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How much is a flywheel puller?

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How do you put a Woodruff key on a crankshaft?

When installing a woodruff key, first press it into the semi‑circular groove milled into the shaft. Next, align the top, flat portion of the key so that it is parallel with the host shaft. During installation, woodruff keys will sometimes slip out of their groove as the mating component is pressed on.

How do I remove a sheared Woodruff key?

1. Try tapping down on one end of the key with a hammer and nail. …
2. Rapidly heating the key with a blowtorch and letting it cool can help loosen it.
3. Remember that these keys are cheap and readily available online or at hardware and auto part stores, so causing damage to it may be necessary.

Why is the pull cord stuck on the pressure washer?

If the starter rope won’t budge when you try to pull it, the engine may be locked up or the recoil starter may have failed. If you tipped the pressure washer on its side recently, oil may have filled the cylinder, preventing the engine from spinning. … Then reinstall the spark plug and try to start the engine.

How do I keep my flywheel from turning?

1. Put one of your pressure plate bolts into the flywheel (so the head is flush with the flywheel, but it doesn’t need to be tight)
2. Place a pry bar, pipe, or some other piece of metal between the bolt head and the ground.

How do you test a flywheel magnet?

Be sure the magnet you are testing is rotated away from the magneto when testing takes place. Hold the screwdriver against the magnet, if the magnet pulls the screwdriver in, the magnet is fine. If it seems weak or does not pull the screwdriver in, the magnet needs to be replaced.

Do I need a flywheel key?

The flywheel on your small engine was originally designed to store the momentum from combustion to keep the crankshaft turning in between the engine’s power strokes. … The soft metal key must eliminate play between the flywheel and crankshaft.

How do I know if my riding lawn mower is locked up?

1. Engine sounds rough.
2. Engine does not start.
3. Blades do not move and are stuck.
4. The cylinder and piston are fixed.
5. Low oil level.
6. Deteriorated fuel quality.

What happens if your flywheel breaks?

If your flywheel is going bad, a smooth pedal is not what you will feel. You may feel vibration as soon as you place your foot on the clutch or when you press down on the clutch. The vibration tends to get stronger as you push on or engage the clutch pedal.

Where is the crankshaft located on a mower?

Located in the “bottom end” of an engine, the crankshaft harnesses the tremendous force of combustion (the violent burning of the air and fuel in the combustion chamber) by thrusting the pistons downward, causing the crankshaft to rotate. This rotation is the power source of an engine.

Is it hard to replace a crankshaft?

However, unlike many other components you can simply remove from around the engine block, removing, handling and installing the crankshaft requires a special procedure. … With the engine out of the vehicle and the rest of the components off the block, you are ready to work on the crankshaft.

Why are flywheels so expensive?

Traditional flywheels have been very expensive because engineers align the natural axis of the wheel’s rotation with the desired rotation of the generator.

Can you drive with a damaged flywheel?

I wouldn’t advise it. Generally 2 things can go wrong with a flywheel. Either stripped/broken ring gear teeth around the rim, or warped/cracked/out of balance. The stripped gear teeth can leave you stranded when starter can’t engage it to crank the engine over.

Can a flywheel damage a starter?

It depends on how the flywheel is damaged. It’s not unusual for the damage to interfere only with starting the engine, because some of the teeth around the rim are damaged. These teeth engage with the teeth on the electric starter motor to spin the engine when starting it.