What is a flywheel key?
^ Photo 1. Various Flywheel Keys The flywheel key is a small metal part (see Photo 1) that locates the flywheel in the correct position relative to the crankshaft, and thereby to the piston.
How do I know if my flywheel key is bad?
Always check for damage by removing the flywheel to inspect the key and the keyway, the key's slot on the crankshaft. The soft metal key must eliminate play between the flywheel and crankshaft. How do I remove the flywheel key? 1.
Do you know what a flywheel is?
If you have only driven automatic transmission vehicles before then you have probably never heard of flywheels. Flywheels are usually only found in manual transmission vehicles. Flywheels on cars and trucks are attached to the back of the engine between the engine and transmission.
Why do I need flywheel key shears?
Step 1: Why? The flywheel key shears to protect the crankshaft from twisting, which would cause a very expensive repair. 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.
How do you remove the flywheel from a Briggs and Stratton engine?
0:072:27How To Remove The Flywheel On a Lawn Tractor with Briggs & Stratton ...YouTubeStart of suggested clipEnd of suggested clipIf you use the impact wrench you don't need to lock the engine. And all the bolts out and previouslyMoreIf you use the impact wrench you don't need to lock the engine. And all the bolts out and previously remove the two half-inch bolts here that hold the plastic cover on the flywheel.
What does a sheared flywheel key look like?
0:203:17Lawnmower Will Not Start - You Will Never Guess Why! - YouTubeYouTubeStart of suggested clipEnd of suggested clipAnd are not familiar with what a sheared flywheel key looks like I have one here that is partiallyMoreAnd are not familiar with what a sheared flywheel key looks like I have one here that is partially sheared.
What does a flywheel key do?
The flywheel key shears to protect the crankshaft from twisting, which would cause a very expensive repair. 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.
How do you replace a sheared flywheel key?
4:5211:47How to Fix a Sheared Flywheel Key! - YouTubeYouTubeStart of suggested clipEnd of suggested clipAnd then go ahead and slip in your key until it gets tight. And now that we have our flywheel offMoreAnd then go ahead and slip in your key until it gets tight. And now that we have our flywheel off it's a good time to take a little bit of nickel anti-seize. And put it onto your crankshaft.
How do you remove a flywheel without a puller?
1:304:42Small Engine Repair: How to Remove a Flywheel without a Puller on a ...YouTubeStart of suggested clipEnd of suggested clipAnyway put the the pipe eye underneath the flywheel. Apply some pressure take a ball-peen hammer.MoreAnyway put the the pipe eye underneath the flywheel. Apply some pressure take a ball-peen hammer. And hit the end of the crankshaft. And that's how you remove a flywheel without a flywheel puller.
How do I remove a flywheel key?
1:233:07Replacing the Flywheel Key on a Lawn Mower - YouTubeYouTubeStart of suggested clipEnd of suggested clipTool remove the nut and pull the flywheel off the crankshaft. Remove any remnants of the flywheelMoreTool remove the nut and pull the flywheel off the crankshaft. Remove any remnants of the flywheel key from the crankshaft. Line up the notch in the flywheel with a slot in the crankshaft.
How do you change a flywheel key on a riding lawn mower?
1:583:41Replacing a Flywheel Key on a Riding Lawn Mower - YouTubeYouTubeStart of suggested clipEnd of suggested clipAfter freeing the flywheel remove the flywheel puller and flywheel bolt pull the flywheel off theMoreAfter freeing the flywheel remove the flywheel puller and flywheel bolt pull the flywheel off the crankshaft remove the remnants of the flywheel key from the crankshaft.
How do you remove a Briggs and Stratton flywheel without a puller?
8:5610:49How To Easily Remove A Flywheel - YouTubeYouTubeStart of suggested clipEnd of suggested clipSo use a big solid bar. It don't have to be brass it could be steel. And a lot of times you don'tMoreSo use a big solid bar. It don't have to be brass it could be steel. And a lot of times you don't even have to pry on it a lot of times you can just hold it up.
What causes kickback on a lawn mower?
A lawnmower engine commonly kicks back when the shear key breaks. The shear key commonly breaks because the blade has kit a solid object and come to a sudden stop. Common symptoms of broken shear key include: Engine won't start.
Why do you need a flywheel key?
The flywheel key shears to protect the crankshaft from twisting, which would cause a very expensive repair. 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.
How to change flywheel key?
Place the flywheel on the crankshaft. It should slide down smoothly over the new key. Oil the threads on the end of the crankshaft. Place the cup, the washer, and the nut onto the crankshaft. Begin to tighten. Never pry against the flywheel cool ing fins. They break easily. Turn the flywheel a couple of times to make certain it turns smoothly and nothing is obstructing it. If you did not tie back the dead man's clutch, you will hear a terrible scraping sound. Torque the flywheel nut. The recommended specifications are usually around 33 foot pounds. On some engines the figure will be 35 or 39 foot pounds. In general, if you are shearing a lot of flywheel keys for no reason, the nut is not yet tight enough.
How much torque do you need for a flywheel nut?
Torque the flywheel nut. The recommended specifications are usually around 33 foot pounds. On some engines the figure will be 35 or 39 foot pounds. In general, if you are shearing a lot of flywheel keys for no reason, the nut is not yet tight enough.
What is the key for a Tecumseh mower?
The key shown is part number 611004. It has a wider, thicker portion at one end. That end faces down on my engine.
What goes around the fill tube on a car?
There is a rubber gasket that goes around the fill tube. It is easy for this to become separated from the fill tube during removal. Be sure this gasket is in place before you finish. When all of the shrouds are back in place, untie the dead man's clutch and put the spark plug wire back onto the spark plug.
Do you need a flywheel puller?
Most people will not have a factory issue flywheel puller in their toolbox. You do not need one, if you are careful. Remove the starter rope cup and put the nut back onto the threaded portion of the crankshaft. Turn it until the face of the nut is exactly flush with the top of the crankshaft.
Can a flywheel key be replaced?
Your flywheel key is sheared and it needs to be replaced. The flywheel moved and sheared the key. Now the engine timing is very much incorrect. The spark comes at a time that makes the engine want to run backwards, but it cannot. As a safety precaution, always remove the spark plug wire before working on a small engine.
How to remove flywheel key?
How do I remove the flywheel key? Step 1: Disconnect the spark plug lead and secure it away from the spark plug. Then, loosen the bolts holding the shroud in place and remove the shroud. Step 2: If the engine is equipped with a flywheel brake, remove any cover and disconnect the outer end of the brake spring.
What is a small engine flywheel?
What is a small engine’s flywheel? 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. Flywheels on today's small engines serve several other purposes. The fins help cool the engine by distributing air around the engine block.
How to align a key on a crankshaft?
Place the flywheel on the crankshaft and look through the flywheel hub to align the keyways on the flywheel and crankshaft. With the flywheel in place, place the key in the keyway; it should fit securely. If you feel play, check to see if the key is upside down.
Where are magnets mounted on a flywheel?
Magnets mounted on the outside surface of the flywheel are required for ignition. On engines with starter motors, lights or other devices, magnets mounted inside and outside are at the heart of the electrical system.
How do the fins work on a motor?
The fins help cool the engine by distributing air around the engine block. The fins also blow air across the air vane on a pneumatic governor, maintaining the desired engine speed (see " Governor System "). Magnets mounted on the outside surface of the flywheel are required for ignition.
Why is a flywheel important?
The flywheel provides mass for rotational inertia to keep your car’s engine running. Otherwise, the engine will stall when you let your foot off the accelerator. It balances the engine. A flywheel is specifically weighted to the car’s crankshaft to smooth out the rough feeling caused by even a slight imbalance.
Why is the flywheel so rigid?
It’s extremely rigid to prevent flexing or warpage during use. The edge of the flywheel has a row of gear teeth that engage with the engine’s starter motor. The flywheel is firmly bolted to a flange on the transmission side of the crankshaft inside the bell housing.
What causes a flywheel to crack?
It causes clutch slippage and excessive friction and heat. Warpage or hot spots can result, creating a vibration on engagement and acceleration. In extremely rare cases, a flywheel can crack due to hard use in high-performance ...
How does a starter work?
The starter motor engages the starter ring on the edge of the flywheel to begin engine rotation. Most importantly for drivers, the flywheel connects the engine with the transmission via a clutch to transfer power to the wheels. When your foot is on the clutch pedal, the clutch disc is disengaged from the flywheel.
What happens when you put your foot on the clutch pedal?
When your foot is on the clutch pedal, the clutch disc is disengaged from the flywheel. This is how a car can sit still at idle with the shifter in gear, or how a car can coast to a stop. But when the pedal is released, the clutch disc will press firmly against the flywheel.
How much does it cost to resurface a flywheel?
Resurfacing a flywheel is, on average, around $500 to $650 for the labour involved. If a replacement flywheel is required, the average repair cost is $700 to $1,200 depending on the make and model. It’s also a great time to change the clutch if it’s nearing time to replace it.
Can a flywheel leak oil?
Among the most common flywheel problems that can come up is contamination. A leaking rear main crankshaft seal or a transmission front input shaft seal can leak oil onto the flywheel.
What is a flywheel in a car?
Every car with a manual transmission has a mechanical device called a flywheel. Flywheels are heavy, balanced metal disks that store rotational energy. Since heavy spinning objects have high inertia (that is, resistance to change in velocity), flywheels keep your engine running smoothly even when torque delivery is inconsistent or changes quickly, ...
Where are flywheels located?
Flywheels are usually only found in manual transmission vehicles. Flywheels on cars and trucks are attached to the back of the engine between the engine and transmission. Flywheels provide an additional friction surface for the clutch and come with teeth that engage with the starter. When you turn the key, the starter motor turns the flywheel, ...
Why is it important to have a flywheel?
It is important for a manual vehicle to have a flywheel for gear changes and clutch engagement. Without a flywheel, the vehicle would likely stall when you engage the clutch to move the vehicle from a standstill. This is because the engine speed would drop too fast without all the angular momentum the flywheel provides.
How much does it cost to replace a flywheel?
The replacement cost of a flywheel will depend on the make and model of your vehicle. You may get lucky and find the cost of a new flywheel to be only $40 or so. However, there are some flywheels which will cost up to $400 or more which are made up of stronger and lighter materials than just steel.
What happens if oil is put on the flywheel?
If oil or grease were to make its way onto the friction surface of the flywheel, it would impact the clutch’s ability to engage with the flywheel and grab it without slipping, even when the clutch should be fully engaged (with your foot off of the clutch pedal).
Why is my flywheel leaking?
If you’ve ever overheated your flywheel or driven too long with a clutch that was on its last legs, it is very likely that you have damaged the flywheel due to excessive heat or metal on metal wear. Clutches that are worn down to the rivets will damage the flywheel.
What does it mean when your gears slip?
1) Slipping Gears. If you shift to a new gear and then notice that the engine speed (RPM) increases much faster than your ground speed, this is called gear slippage. Since the flywheel and the pressure plate both have friction surfaces that are designed to grip the clutch, a slipping flywheel may feel like a slipping clutch.
What does a flywheel look like?
A flywheel looks like a simple part in your car, but it actually has many purposes, especially in more modern car models. If you suspect that your vehicle’s flywheel is wearing out, you need to replace it as soon as possible before the problem worsens and starts to affect other components in your vehicle. But what is a flywheel, and how do you know ...
Where is the flywheel located?
Flywheel Location. Your vehicle’s flywheel is always located towards the engine’s rear, directly between your engine and transmission. The housing completely encases the flywheel, so you won’t see the whole thing unless you remove the engine’s transmission.
What does a flywheel do when you depress the clutch?
When you depress the clutch, what you’re actually doing is disconnecting the flywheel from the transmission.
Why is my flywheel not shifting?
Problems Shifting Gears. While it’s unlikely that a broken flywheel would be the cause, it’s not impossible either. If you’re having trouble shifting gears, it means your flywheel is extremely warped, and you’ve probably had some problems you’ve been ignoring for a while.
Why is a flywheel important?
It helps start the engine. It connects to transfer power from the engine to the transmission (along with the clutch) The first function of a flywheel is to keep the engine in motion even when you stop accelerating. It’s why the flywheel has to be significantly heavier than a flex plate.
How much does it cost to replace a flywheel?
The average flywheel replacement cost is between $500 and $2500, depending on the car model and if you replace the clutch at the same time. Expect $200 to $1000 in parts and $400 to $1500 in labor.
Does a manual flywheel have a torque converter?
Because while an automatic engine has a torque converter, a manual one does not . The flywheel servers this function. From there, it provides a natural counterweight to the crankshaft. This counterweight is built right into the flywheel, which is why it’s so crucial that you get a vehicle-specific flywheel for your vehicle.
