Briggs& Stratton engine will not turn over

JimP2014

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So obviously the flywheel key is sheered so there has to be reasons for that and it probably happened the very first time a few days ago after I put the flywheel back so it probably broke pretty quickly. So there has to be a reason for that. I'm going to say one reason might be I didn't torque it to at least 80 foot pounds. I just wonder before I get another flywheel key and put it back if there's anything else I should look for. I did see copper windings and that's the thing that goes around the flywheel so to speak. But it's part of the engine and I'm hoping that only is for charging the battery and nothing else. I don't know if any of those windings are broken because I don't look that closely but I will in a while. So what could be the possible causes of a sheered flywheel key?

Jim

So obviously the flywheel key is sheered so there has to be reasons for that and it probably happened the very first time a few days ago after I put the flywheel back so it probably broke pretty quickly. So there has to be a reason for that. I'm going to say one reason might be I didn't torque it to at least 80 foot pounds. I just wonder before I get another flywheel key and put it back if there's anything else I should look for. I did see copper windings and that's the thing that goes around the flywheel so to speak. But it's part of the engine and I'm hoping that only is for charging the battery and nothing else. I don't know if any of those windings are broken because I don't look that closely but I will in a while. So what could be the possible causes of a sheered flywheel key?

Jim
Briggs& Stratton 5002k Is what I ordered about a week ago and the only thing I could say is they're about a half inch long. Your choices are a half inch long or I think 1 in long. So the one I had for 3 years and it's probably still good but I can't find it is one half inch long so I got the same length. Maybe I should have gotten the one that is 1 in Long
 

ILENGINE

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So obviously the flywheel key is sheered so there has to be reasons for that and it probably happened the very first time a few days ago after I put the flywheel back so it probably broke pretty quickly. So there has to be a reason for that. I'm going to say one reason might be I didn't torque it to at least 80 foot pounds. I just wonder before I get another flywheel key and put it back if there's anything else I should look for. I did see copper windings and that's the thing that goes around the flywheel so to speak. But it's part of the engine and I'm hoping that only is for charging the battery and nothing else. I don't know if any of those windings are broken because I don't look that closely but I will in a while. So what could be the possible causes of a sheered flywheel key?

Jim
Most common causes of sheared flywheel keys on riders is oil or grease on the crankshaft taper or improper torque. Unless you hit something that causes a sudden stop of the flywheel. And I have had them shear and rotate the flywheel 180 degrees on startup when not set with a proper torque wrench.

Looks like Briggs dealer site is saying the flywheel torque is supposed to be 110 lb/ft or 149 Nm So that may be the reason for the sheared flywheel key.
 
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JimP2014

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Briggs& Stratton 5002k Is what I ordered about a week ago and the only thing I could say is they're about a half inch long. Your choices are a half inch long or I think 1 in long. So the one I had for 3 years and it's probably still good but I can't find it is one half inch long so I got the same length. Maybe I should have gotten the one that is 1 in Long
796335 Is what I should have ordered. I think it's the original Briggs& Stratton part. This one is listed as a 1/2 in Long and maybe I need to order that one. I have no clue if the other two I have which are not the right model is why it's sheered a few days ago
 

JimP2014

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796335 Is what I should have ordered. I think it's the original Briggs& Stratton part. This one is listed as a 1/2 in Long and maybe I need to order that one. I have no clue if the other two I have which are not the right model is why it's sheered a few days ago
I didn't see your reply the first time around and I see what you're saying and I'll have to reread it. But what are your thoughts about using in theory the correct length? But according to Briggs& Stratton I bought three of the wrong kind even though they're a half inch long?

Thanks,
Jim
 

JimP2014

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So obviously the flywheel key is sheered so there has to be reasons for that and it probably happened the very first time a few days ago after I put the flywheel back so it probably broke pretty quickly. So there has to be a reason for that. I'm going to say one reason might be I didn't torque it to at least 80 foot pounds. I just wonder before I get another flywheel key and put it back if there's anything else I should look for. I did see copper windings and that's the thing that goes around the flywheel so to speak. But it's part of the engine and I'm hoping that only is for charging the battery and nothing else. I don't know if any of those windings are broken because I don't look that closely but I will in a while. So what could be the possible causes of a sheered flywheel key?

Jim

1000009862.png
 

JimP2014

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I found this in another form and I'm pretty sure the issue about taper applies to this engine completely. So having said that, I'm wondering if I just use the flywheel keys that I bought already rather than buying the specific model number that Briggs and Stratton recommends. This is kind of where I'm at right now with this. Try one of the brand new keys I have or just ordered the absolutely correct one and wait for that to arrive and pick the whole thing up again later?

"This is a tapered shaft, tapered flywheel fit. The key does nothing but line up the flywheel for timing purposes. It's not strong enough to hold while the engine is running. The only purpose for the key is to line up the flywheel until the nut is tight. You can run this engine without a flywheel key if the flywheel nut is torqued properly."
 

JimP2014

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1000009863.png
And of course I find this. After I make posts to this forum. I got to figure out which one I have.
 

Mark H_NO

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Hi Jim,
Sheared key can be from insufficient torque, or something suddenly blocking rotation, such as hitting a big root with the blade. I think that's how I did mine. Ilengine did say "while checking the flywheel key make sure the ignition module isn't hitting the flywheel which can cause spark under compression issues among other things." So check that if you can. I believe someone said the coils are for the charging system.
 

JimP2014

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Hi Jim,
Sheared key can be from insufficient torque, or something suddenly blocking rotation, such as hitting a big root with the blade. I think that's how I did mine. Ilengine did say "while checking the flywheel key make sure the ignition module isn't hitting the flywheel which can cause spark under compression issues among other things." So check that if you can. I believe someone said the coils are for the charging system.
Mark Mark, yes, as far as the blade, I don't think that's an issue at all because the PTO clutches off, but I could freely spend the blades just to make sure there's nothing going on down there. But generally speaking, they're not an issue unless you decide to engage the PTO clutch, but I will reread the other stuff you got
 

Mark H_NO

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The blade stopping from a blockage can shear the key. That's all I was talking about. If it sheared without ever driving the blades, obviously that didn't happen. Lack of torque, or lube on shaft as Ilengine mentioned probably did it.
 
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