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"governer kicks in"?


Simpleton7016

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"in sickness and health" - gosh am I ever honoring that vow lately! My wife is sick and sleeping right now. And the kids are sick and awake. Which means I am awake! It is a bit frustrating since I only have off two days a week (Sat and Sun) and I actually get less sleep on those days. But alas, here I am up in the middle of the night watching Elmo, cleaning up vomit and cuddling with two drippy young men. Take note Shanon!:) And complain as I may, this is one of the best parts of fatherhood since you get to realize how much everyone loves you. Anyway, since I am not asleep, I have been using the night to search the archives and learn some things. But I have a question which will further display my relative lack of mechanical knowledge. Fortunately, humility is one of my "strong suits" (Sheepshead anybody?) Like everyone else here, I love my tractors and especially love the fact that they are easy to work on. It doesn't necessarily follow that I know them inside and out....especially when it comes to the engine functionality. My question is this: What is the physics behind the term "when the governor kicks in"? I have seen a lot of posts talking about the "governor". And I remember the video link that Kent posted last winter of his snowblower in action. Someone commented that it "sure sounds sweet when the governor kicks in". I know what the sound is and further, I know when my "governor kicks in", but I don't know what that really means? I agree, it is a cool "sound" and it seems to translate into "extra power", but I don't know or understand what my engine is actually doing when the "governor kicks in". Mine definitely "kicks in" when I am snowblowing, rototilling and if I go through a particularly thick patch of grass with the deck and vacuum engaged. Do all engines have a governor? Is it good for the engine? Is it bad for the engine? Does it place any additional stress on the engine? Is it something that should be minimized to preserve the longevity of the engine? Is it something that can be adjusted or is it an internal mechanism and/or inner functionality of all engines?
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Erik, Governors are installed on most "industrial" engines to maintain a given RPM under varying loads by controlling the fuel source. Obviously when the point is reached where engine is overloaded the governor cannot compensate and engine speed falls off-the governor is telling the carb "more fuel" and it is allready at max.... It is an internal mechanism where centrifigual force is balanced by an external spring(s) for a desired engine speed. Less spring tension means less speed... Generally across the board most engines shouldn't be loaded above 80% of their HP/Torque rating for extended periods or engine life drops off fast. Dont worry about short periods of hearing that Briggs "thump"...I like it too- Ok....you asked the time and I told you how to build a watch :) Brent
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The governor tries to maintain a constant rpm set by the throttle. The governor is in between the your throttle desires and the carb in respect to the the throttle linkages. in other words you are not opening and closing the carburator with the throttle position you are only applying a different amount of spring pressure to overcome the amount of pressure applied to the governor arm by weights inside the engine. the more rpms the more static pressure is applied to the arm to return it to a neutral state (closed throttle,idle). Actually when the "Governor kicks in" it is really relaxing it's pressure (kicking out) on the arm (because of less rpm's) allowing the throttle plate in the carb to open farther allowing in more gas/air mixture to raise/maintain the rpm's. I hope this helps and doesn't confuse you more.
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Good point Rich, I'll bet there aren't too many farmers or business owners shedding tears over my two days off!:) Brent thank you for your explanation and for one using one of my favorite sayings - one that I use on my wife all the time (building a watch).
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Another analogy that may help explain a governor is comparing it to the cruise control on a vehicle. Without the cruise on, you are constantly pressing or releasing the foot feed to maintain a set speed unless on a perfectly flat slab and steady winds. Without a governor on a small engine, you'd constantly be adjusting the throttle in varying engine loads.
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Erik, let us set up a few hours and I'll stop by, show you the hands on theory and then see if your machinery is doing what it should. Shouldn't take more then three or for six packs of Leine's. He He he YOUR MENTOR.
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Well, I get two days off, and for the last few 'days off', I have pressure washed and sealed the decks, painted the outside doors, cleaned up the yard, cut a few bushes(with a chainsaw) My trimming leaves a lot to be desired for shape! I did get a few minutes in between to finish cleaning my gearbox and painting it. I even pressure washed the tranny for painting, and have the first light coat on it. Personally, days off are about as bad as days at work, so I am not really desirous of 'days off! As for your governor kicking in. If it weren't for the governor, you would likely not be able to cut grass, blow snow, or even move the tractor. Your governor is the part of your engine that regulates the set speed. If anything causes any extra 'pull' on your engine, the governor acts to speed the engine up enough to keep it running, instead of dying instantly, when the extra force is applied to the attachment of a hard pull.
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