Broken funs on the flywheel?

#1
I was working on an old 5HP briggs today and discovered it had a broken fin on each side of the fly wheel as if someone broke them trying to remove it. :doah:

Is it a really big deal?

I got it running and was just wondering if I can get away with it like that for awhile. :confused:
 
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minidragbike

Supporting Speed Nut!
#5
It will run OK.
I'm guessing your mtor isn't turning very high RPM anyway. If you were turning 7,000+ RPM you would be pushing it.
 
#8
I was working on an old 5HP briggs today and discovered it had a broken fin on each side of the fly wheel as if someone broke them trying to remove it. :doah:

Is it a really big deal?

I got it running and was just wondering if I can get away with it like that for awhile. :confused:
I've had one with a broken fin I've run for years. No boom. If you had a bunch of them broke it might throw the balance off. All they do is move air to cool the engine.
 
#9
Thanks guys, this engine is to old and worn to run hard, just a cuiser untill I rebuild it sometime and then I''l replace the wheel.

Thanks for the link Josh. :thumbsup:
 

minidragbike

Supporting Speed Nut!
#11
I run a flywheel that is missing about 6 fins every weekend. I took the fins off on purpose.

But of course I don't know what I'm talking about.
 
#12
DO NOT USE THAT FLYWHEEL!!!!

If it has broken fins you can imagine the kind of beating this flywheel endured. Even a small hit or a prying motion WILL develop cracks in the cast iron. These cracks are invisible to the naked eye, but they are there and they grow bigger every time you run the engine.

If you use that flywheel, even at a low rpm, it WILL eventually explode like a grenade. It can even happen at idle! Even starting the engine puts an enormous amount of stress on the flywheel during the first revolutions (0 to 1400 rpm in half a second!). And when it explodes it ain't a small explosion. It can rip your arm, leg or head right off.

So, for your own safety and for the safety of those around you, please cut that thing in half so no one can ever use it again and throw it in the trash can.

Again, I'm not kidding, a damaged flywheel can KILL when it goes boom. Be careful.
 
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minidragbike

Supporting Speed Nut!
#13
I see I'm going to have to take pictures again.

I'm only guessing 6 fins from what I can remember. There maybe more?

I turn this motor 7,500-8,300 RPM every weekend. And I ran it on the minimoto run for 20 miles.
 
#14
MDB - I was not targeting you personally or anything. I just think no one should take any chance when it comes to safety. Yes, you have run a damaged flywheel for years without a problem, I have no trouble believing that. But does that make it safer? I'm afraid no.

I mean, you can drive a car with only 1 lug nut per wheel for all your life without a problem, but you are definitely not on the safe side. Please, get rid of that flywheel before something happens. If it blows up at 8000 rpm, you sure won't be there to tell the story.
 
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