Awesome guide to modding Briggs 5 hp flatheads

#21
[/COLOR]I know these posts are old but want to throw in my opinion

If the aluminum flywheel came off of a lawnmower's vertical shaft, then you cannot use it. Vertical shaft lawn mower engines use the grass cutting blades as second flywheels. The aluminum flywheels off of lawnmowers will not work because they are to light.
True and false the blade does spin as a sort of second flywheel............ kind of. But a briggs mower will run with out a blade on it, the big problem is the timing will be off on most.

NEVER USE ONE.ITS A TIME BOMB WAITING TO GO OFF.if you prefer,use the cast iron one 3 or 3.5 hp. with a stock unmodified engine,they'll last as long as you keep it under 7000 rpm.[completely stock engines won't rev to 7k anyway.]
how is aluminum any worst than cast iron? If nothing else it is better. Aluminum is softer so in theory it will be less likely to explode vs iron. This being said stock aluminum fly wheels are cast not billet so the performance strength and reliability will not be there.

I have not don't an aluminum flywheel my self but I am going to attempt it idle may be an issue though


edit

after some researching this afternoon I think the aurgument for not running aluminum is because of the tendancy of the magnents to become unbonded this is a valid concern but it seems like everyone that makes a decent point for this arguement also says the cast iron is just as dangerous, most real aurguments centered around the B & S animal gen 1 flywheel
 
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#23
You can slightly bore out the side cover at the output shaft, and press in a small needle bearing. I had a 3HP Briggs that had this done at some point.
 
#24
Bull x 3!
Please get your facts straight.
Non of the above is factual.
Do you guys make this stuff up as you go along? OR, do you just hear it and pass it along?
1. The engine will work, But the flywheel is not heavy enough to properly balance the engine.

2. They will not explode, but eventually, they will break apart when the engine is running.

Obviously the correct terminology was not used in the other posts, but you know as well as I do, most of the information is true.
 
#30
1. The engine will work, But the flywheel is not heavy enough to properly balance the engine.

2. They will not explode, but eventually, they will break apart when the engine is running.

Obviously the correct terminology was not used in the other posts, but you know as well as I do, most of the information is true.
@Ibanez616...Please tell me where you get this trash from...or more prosaically...did you just make it up? One thing is for sure... you have NO experience. Any state of intelligence would tell anybody that all of what you say/type is suspect.
Garbage in, garbage out.
 
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#32
@Ibanez616...Please tell me where you get this trash from...or more prosaically...did you just make it up? One thing is for sure... you have NO experience. Any state of intelligence would tell anybody that all of what you say/type is suspect.
Garbage in, garbage out.
Lmfao. Biggest troll ever. You come back to a thread almost 20 days later to try and act like your somebody. Yeah right, Get a life. :laugh:
 
#35
Lmfao. Biggest troll ever. You come back to a thread almost 20 days later to try and act like your somebody. Yeah right, Get a life.
It's been my experience that folks with no experience resort to this kind of post. Why? Because you don't have the answers.
The engine will work, But the flywheel is not heavy enough to properly balance the engine.
In 4+ decades, I have never had any balancing issues.
They will not explode, but eventually, they will break apart when the engine is running.
I (or you) have never experienced this.
I can prove what I post. Can you?
Seen Elvis lately?
 
#37
I could hear the yelling from the other side of the internet...Not really sure what you guys are talking about but what do boats have to do with 5hp flatheads?:biggrin:
 
#38
It's been my experience that folks with no experience resort to this kind of post. Why? Because you don't have the answers.
In 4+ decades, I have never had any balancing issues.
I (or you) have never experienced this.
I can prove what I post. Can you?
Seen Elvis lately?
Again, who are you? Nobody. You have no idea who I am or what my capabilities are. I don't have to prove a thing to you, or anybody else on this forum for that matter. You can reply whatever you want, but I'm not going to continue a pointless argument with a self righteous want to be expert.
 
#40
It's been my experience that folks with no experience resort to this kind of post. Why? Because you don't have the answers.
In 4+ decades, I have never had any balancing issues.
I (or you) have never experienced this.
I can prove what I post. Can you?
Seen Elvis lately?
i have no idea who you are nor do i care.
please do not post things that make our riding units unsafe. there are kids,children riding these and people watching them.
I can only hope the administration sees this thread and shuts you off.
or maybe you just go away.
 
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