Is it safe to run Briggs & Stratton 5 hp engine without governor?

7394

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  • / Is it safe to run Briggs & Stratton 5 hp engine without governor?
Likely, bad history with them.
 

sharnett

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  • / Is it safe to run Briggs & Stratton 5 hp engine without governor?
So this "air-vane governor" is something you attache outside the engine, near the fly-wheel? Sounds like you wouldn't need to open up the engine to do this mod. Does Briggs and Stratton actually make an air-vane governor for this engine, or is this more of an aftermarket hack? I'm trying to figure out which is the easiest/cheapest solution, restore the factory governor gear which requires taking apart the engine cover, or this "air-vane" mod.
I made the governor out of sheet metal. It is outside the engine, inside the cowling. The force of the cooling air blowing past the vane works against the governor spring. The faster the engine turns, the more more air flows past the vane, pushing the throttle closed. I didn't invent this, though I certainly admire its elegance and simplicity. It's used on a lot of old Briggs engines and you can look up "air vane governor" on line.
 

slomo

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  • / Is it safe to run Briggs & Stratton 5 hp engine without governor?
I recently got hold of a very hold and rusted chipper/shredder. It's a craftsman model# 247.797851, I believe from 1990.
Previous owner said it hasn't been used for years, but it did run fine before that. I cleaned the carburetor, replaced the spark plug and lo and behold the engine fired up.
However, this is when I noticed the engine has no governor. In the attached pictures, you can see where the governor rod is supposed to be, there is simply a bolt.
I figured the previous owner removed the governor on purpose and ran the engine by manually adjusting the throttle.
My only worry is, how do I know I'm not running at too high rpm? Is there an easy way to tell you are running at slow enough rpm to be safe?
It's very safe to run without a governor. Just keep the rpms under 3600. Easy right?

Personally I would fix the gov proper and drink a few cold beers.
 

7394

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  • / Is it safe to run Briggs & Stratton 5 hp engine without governor?
Didn't work for my 1st Briggs as a kid.
 

kinwin

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  • / Is it safe to run Briggs & Stratton 5 hp engine without governor?
I made the governor out of sheet metal. It is outside the engine, inside the cowling. The force of the cooling air blowing past the vane works against the governor spring. The faster the engine turns, the more more air flows past the vane, pushing the throttle closed. I didn't invent this, though I certainly admire its elegance and simplicity. It's used on a lot of old Briggs engines and you can look up "air vane governor" on line.
Thanks for the detailed explanation. I'll probably use the engine as-is for now, but I'll keep in mind all the options to restore the governor. Making your own air vane sounds same or more challenging than a factory restoration to me. Who knows, maybe in the future I'll feel brave enough to take on this task, but until then I'm content with what I've got so far. Thanks again for all the useful information.
 
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