why does my flywheel key keeps shearing

by Marquise Towne Published 3 years ago Updated 2 years ago

flywheel keys keep shearing.

bebuzz69
Rivets. If the keyway in both the crankshaft and flywheel are good, the main cause for shearing would be not properly torqueing the flywheel nut.
bebuzz69
ILENGINE
bertsmobile1. You have most likely damaged the key ways. ...
SeniorCitizen. By using a impact you may have cracked the flywheel.

Rocky J. ...

ILENGINE. ...

bebuzz69. ...

Full Answer

What causes a flywheel key to shear?

Re: what causes a flywheel key to shear?? The key is shearing because you're asking it to hold the flywheel in place while running. The key should only be for locating the flywheel correctly before bolting it on. The fly wheel should be held on to the crank by pressing it onto the snout of the crank.

What keeps shearing on Briggs and Stratton 331877?

Flywheel key keeps shearing on Briggs and Stratton 331877-3036-G5 engine So, the flywheel key keeps shearing on my 21 HP model Briggs and Stratton 331877-3036-G5 engine (on a Craftsman lawn tractor).

How to fix a flywheel that won't stay on?

The fly wheel should be held on to the crank by pressing it onto the snout of the crank. There are 2 possible problems. Either you're not torquing the flywheel bolt properly or the taper on the flywheel or crank is bad. If it's the taper you can try to fix it with some compound. Last edited by WaveDemon; 02-13-2011 at 02:20 PM .

What causes the flywheel nut to smear?

Looking from undeneath the flywheel, if the key is smearing the left (counterclockwise) it is caused by a loose flywheel nut. If it's smearing to the right (clockwise), then it's caused by a sudden impact stopping the engine, like a blade hitting something or an object getting caught in the drive belt.

Can a sheared flywheel key cause no spark?

0:203:17Lawnmower Will Not Start - You Will Never Guess Why! - YouTubeYouTubeStart of suggested clipEnd of suggested clipAnd what that means is that the flywheel key is not totally lined up with the keyway hole on theMoreAnd what that means is that the flywheel key is not totally lined up with the keyway hole on the crankshaft.

How do you fix a key on a flywheel?

0:263:07Replacing the Flywheel Key on a Lawn Mower - YouTubeYouTubeStart of suggested clipEnd of suggested clipAnd the housing to keep the crankshaft from turning when you loosen the flywheel nut connect aMoreAnd the housing to keep the crankshaft from turning when you loosen the flywheel nut connect a socket wrench to the flywheel nut and tap it with a hammer to loosen the nut remove.

How do you replace a sheared flywheel key?

4:5711:47How to Fix a Sheared Flywheel Key! - YouTubeYouTubeStart of suggested clipEnd of suggested clipAnd now that we have our flywheel off it's a good time to take a little bit of nickel anti-seize.MoreAnd 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 keep a Woodruff key in place?

To keep a woodruff key in place while installing a mating component, ensure that it is situated tightly in the key seat. Since woodruff keys are made to tight tolerances, they often require a press fit into their seat.

How do you remove a sheared Woodruff key?

You can try tapping a nail on one end of the key, drilling into the center of the key and removing it with a nail, or even heating the key up with a blowtorch and letting it cool repeatedly to loosen it. Remember that damaging the key is a far better alternative than damaging the shaft or other part around the key.

How do you seat a flywheel?

2:143:41Replacing a Flywheel Key on a Riding Lawn Mower - YouTubeYouTubeStart of suggested clipEnd of suggested clipPosition the washer over the crankshaft hole thread the flywheel bolt into the crankshaft. And handMorePosition the washer over the crankshaft hole thread the flywheel bolt into the crankshaft. And hand tighten. It. Use a torque wrench to tighten the flywheel nut to one hundred foot-pounds.

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.

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.

How do you remove a flywheel without a puller?

1:304:42How to Remove a Flywheel without a Puller on a Harbor Freight Predator ...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 tight should a woodruff key be?

It is important for key to be somewhat snug and stable in the key seat. If key is not snug/stable then key can easily slide out of key seat due to the curved profile on the bottom. This is very inconvenient in cases where it is difficult to see as the pulley is installed.

Do Woodruff keys wear out?

Woodruff keys tend tend to last forever unless they develop a bit of looseness which then develops quickly. Check the keyways (both in the shaft and in the gear).

Which way does a woodruff key go?

If you look at the end of the crankshaft slot you will see it tapers as it gets closer towards the block and the taper is upwards, so the key goes in with the tapered side facing down and the two tapers fit each other tight so the key doesn't slide too far back.

How do I fix my keyway?

0:481:38Worn and Broken Keyway Solutions - Belzona® - MPT - YouTubeYouTubeStart of suggested clipEnd of suggested clipSolution by using a belzoni metallic polymer a damaged keyway can be rebuilt in place eliminating.MoreSolution by using a belzoni metallic polymer a damaged keyway can be rebuilt in place eliminating. The need for costly.

How do you change a flywheel key on a Briggs and Stratton engine?

2:184:01Briggs & Stratton Lawn Mower Small Engine Flywheel Key 222698SYouTubeStart of suggested clipEnd of suggested clipAnd insert the new key into the slot tap it into secure. Hold the blade in place with the support.MoreAnd insert the new key into the slot tap it into secure. Hold the blade in place with the support.

How do I change the key on my Craftsman flywheel?

3:206:34Sears Craftsman 21" Lawn Mower Flywheel Key Replacement & Startup!YouTubeStart of suggested clipEnd of suggested clipSo I'm going to put the new flywheel key in got everything cleaned off you also need to tie yourMoreSo I'm going to put the new flywheel key in got everything cleaned off you also need to tie your handle down so you can get this flywheel brake off which is your engine cutoff.

How do you use a flywheel puller?

2:313:59Tusk Motorcycle Flywheel Puller - YouTubeYouTubeStart of suggested clipEnd of suggested clipMake sure you've got a good grip on your tools. Also keep in mind once you've reached the rightMoreMake sure you've got a good grip on your tools. Also keep in mind once you've reached the right amount of torque to pull this off the flywheel should just pop right off.

What happens if you shear the first key?

As said, once you shear the first one it causes damage. Shear the second one and it causes more damage, The third----etc. SO, check the tapers. They must be virtually perfect. The key slots must not be battered. If everything is still serviceable, proceed--

What to do after shearing a key?

Also..... after once shearing a key, the crankshaft and flywheel tapers must be cleaned up, get rid of the burrs, etc. If the flywheel can't set properly on the crankshaft taper it will loosen up and shear again. To torque, one needs the proper torque wrench and socket, and also a strap wrench so as to hold onto the flywheel.

What must a crank and flywheel taper be?

1. Crank and flywheel tapers must be shiny clean and smooth.

How to install a key on a car?

The key must be installed with the straight edge perfectly vertical with the engine's driveshaft, crankshaft, etc, not aligned with the crankshaft taper, and the flywheel must be properly torqued. There should be a notch in the key that must go up. The round part of the key goes in the crankshaft.

Why is my flywheel shearing?

The key is shearing because you're asking it to hold the flywheel in place while running. The key should only be for locating the flywheel correctly before bolting it on. The fly wheel should be held on to the crank by pressing it onto the snout of the crank. There are 2 possible problems. Either you're not torquing the flywheel bolt properly or the taper on the flywheel or crank is bad. If it's the taper you can try to fix it with some compound.

How long to smear flywheel?

Put a smear on the snout, set the flywheel on without a key, and rock. Turn it 30 degrees, and rock some more. Do this for 10-15 minutes. Add more paste occasionally. Be sure to clean all the paste off of everything before final assembly. The snout and flywheel must be spotlessly clean before reassembly.

What engine does the flywheel key work on?

Flywheel key keeps shearing on Briggs and Stratton 331877-3036-G5 engine. So, the flywheel key keeps shearing on my 21 HP model Briggs and Stratton 331877-3036-G5 engine (on a Craftsman lawn tractor).

What key keeps shearing on Briggs and Stratton 331877-3036-G5 engine?

Re: Flywheel key keeps shearing on Briggs and Stratton 331877-3036-G5 engine Monday, March 25, 2019 6:33 AM ( permalink ) 0. Running a rope into the cylinder is a good way to bend the valves and/or push rods.

Why is my key smearing the left?

Does a 2003 17HP lawn tractor start fire?

17hp lawn tractor will not start just big back fire. 2003