No spark

StarTech

Lawn Royalty
Joined
Feb 19, 2020
Threads
79
Messages
10,276
You probably sheared the flywheel key! Remove the starting cover to show the flywheel. Remove the centre nut. If it has a starting cup, remove it and put the nut on so it’s at the top of the crankshaft. Turn the magnet so that it’s on the back right hand side of the engine (by where the cover bolt goes-that area. Take a prybar and put under the flywheel where the magnet would be. Gently take a hammer and hit the top of the nut on the crankshaft while pressing down on the prybar. This should pop the flywheel. Remove the nut and the flywheel and there is a flywheel key. I’m sure you will find that it’s sheared. When you get a new one, put the flywheel on, and you will see the space for the key. Put it in, then the starting cup, washer and nut. To tighten so you don’t shear it again. Hold the blade with one hand and tighten the nut down with the socket and ratchet with the other hand. Put the rest back together. You could also probably take the new coil back and put the old one back on. Note: while working on the machine, remove the spark plug for your safety.
Boy haven't you ever heard of using a torque wrench. Under torquing will allow flywheel to shear the key again while over torquing can damage the flywheel.

Here is an image where someone over torqued with an impact and then try to repair it.
l4dgWyO.jpg
 

lowmow

Member
Joined
Sep 2, 2023
Threads
1
Messages
10
Have you checked the shear pin in the flywheel? If it is even partially sheared you will get no spark.:unsure:
 

Gord Baker

Well-Known Member
Joined
Aug 21, 2018
Threads
1
Messages
349
I recently came to visit my daughter and she said her lawn mower will not run first I replaced the spark plug still no spark then I pulled the pull rope cover off and inspected the coil found that it was Rusty apparently been leaving it outside so I've replaced the coil clean the flywheel and still no spark any help would be appreciated
Try the old spark plug again.
 

Zedo

Member
Joined
Apr 26, 2023
Threads
4
Messages
25
Boy haven't you ever heard of using a torque wrench. Under torquing will allow flywheel to shear the key again while over torquing can damage the flywheel.

Here is an image where someone over torqued with an impact and then try to repair it.
l4dgWyO.jpg
Since that flywheel is spinning at 3600 RPM, that repair job would put the flywheel way out of balance and would vibrate the mower like crazy. Whoever repaired that gets the Darwin award for a mower repair.
 
Joined
Jul 22, 2018
Threads
5
Messages
45
Since that flywheel is spinning at 3600 RPM, that repair job would put the flywheel way out of balance and would vibrate the mower like crazy. Whoever repaired that gets the Darwin award for a mower repair.
Obviously you are not a technician! Most people on here don’t have torque wrenches etc. you can’t put a flywheel out of balance unless you take pieces out of it! I’ve done small engine repair for 38 years, so don’t try an BS me!
 
Joined
Jul 22, 2018
Threads
5
Messages
45
Since that flywheel is spinning at 3600 RPM, that repair job would put the flywheel way out of balance and would vibrate the mower like crazy. Whoever repaired that gets the Darwin award for a mower repair.
A lot of people don’t have torque wrenches. That’s why I stated to hang onto the blade and tighten the nut with a socket and ratchet. He never stated anything about impact guns etc. I’ve done this for 38 years. What are your qualifications? Last count, I have 25 manufactures certification and a large number of awards!
 

Zedo

Member
Joined
Apr 26, 2023
Threads
4
Messages
25
A lot of people don’t have torque wrenches. That’s why I stated to hang onto the blade and tighten the nut with a socket and ratchet. He never stated anything about impact guns etc. I’ve done this for 38 years. What are your qualifications? Last count, I have 25 manufactures certification and a large number of awards!
Then you should know flywheel nuts should be torqued to manufacturers specs. I have 3 push mowers and I torque them at around 55 foot pounds. Sure the 'hold the blade and tighten the nut' will work , and I am an ASE certified auto mechanic for 35 years and every bolt on a vehicle has a torque setting. Just sayin'. I never mentioned anything about an impact gun.
 

mgmine

Member
Joined
Apr 6, 2015
Threads
4
Messages
20
Obviously you are not a technician! Most people on here don’t have torque wrenches etc. you can’t put a flywheel out of balance unless you take pieces out of it! I’ve done small engine repair for 38 years, so don’t try an BS me!
Not wanting to argue but any handy person should own a torque wrench. They are cheap as dirt and you're asking for trouble if you don't use one. https://www.harborfreight.com/hand-...e-10-150-ft-lb-click-torque-wrench-63882.html.
 

peabodyn

Member
Joined
May 4, 2013
Threads
13
Messages
41
Check the engine brake cable if the cable doesn't pull far enough, you'll never get a spark.
 

Alan46

Member
Joined
May 12, 2023
Threads
1
Messages
31
Boy haven't you ever heard of using a torque wrench. Under torquing will allow flywheel to shear the key again while over torquing can damage the flywheel.

Here is an image where someone over torqued with an impact and then try to repair it.
l4dgWyO.jpg
Thanks for the photo!
thats crazy bro!👎🏻
 
Top