Kohler CV491S Governor Problem

Rivets

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First thing I would do, if I were a DIY guy, is to make sure I have the correct governor spring. The IPL shows that the correct part number to be 12-089-24, which is listed as NLA. I’ve found many available on the internet.
 

Freddie21

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Fingers and brains are not in sync. Max is 2900. Svc manual says: "If the high idle, no load speed is 3600 RPM or less -use the #2 hole (count outward from cross shaft).If the high idle speed is greater than 3600 RPM -use the #3 hole (count outward from cross shaft)." Even at the spec provided by StarTech, I'm still low. I can increase the idle a bit.
 

StarTech

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Appears you are working with the unitized throttle assy.

You probably dealing with either a weaken or stretched governor. With the spring NLA you may to shorten it slightly by removing one or more coils and reshaping the end to connect it back up. Remove only enough to get the correct speed. Once too short it is all she wrote.

This way you still have the same spring rate but you putting a little tension on it.
 
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Freddie21

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I moved it to the lower hole. Is that the same as shortening it? If so, it surges, but I don't think it sped up. It is not stretched and hard to stretch. It might be easier to drill a 4th hole in the arm between #2 and #3. I thought about a slightly longer throttle linkage arm.
 

Tiger Small Engine

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I moved it to the lower hole. Is that the same as shortening it? If so, it surges, but I don't think it sped up. It is not stretched and hard to stretch. It might be easier to drill a 4th hole in the arm between #2 and #3. I thought about a slightly longer throttle linkage arm.

How are you measuring the RPMs, with a digital tachometer? I would try to get it around 3200-3300 if it an older engine. As stated previously, 3600 is max. It is very important to have the RPM and governor steady. How you get there, different spring, drilling holes, adjusting springs, is up to you.
 

Freddie21

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Measuring the steady speed with an induction type (spark plug wire) electronic tach. High quality $15 ebay product.
 

Freddie21

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With all your help, I have cured the problem. A complete adjustment of the throttle plate was necessary. Thanks again
 

TobyU

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Anytime you're dealing with a governor issue, you always need to stop everything else and do a static governor adjustment.
You can't adjust these things a little bit here or a little bit there like many people think they can so they will loosen them and move them just a little bit and all of that trying to adjust engine speed which is entirely the wrong way of trying to accomplish what they're looking for.
A governor needs to be set properly from its basic static governor adjustment position.
Then you can go about spring tensions, different holes, or bending tangs or whatever designs have been Incorporated by the manufacturer to adjust RPMs.
 

Freddie21

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The static adjustment was correct. It was the plate that was out. The tech used the wrong engine manual and the correct plate was not shown. With the Forums help, I got the correct manual and adjustment procedure. Thanks again.
 

TobyU

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The static adjustment was correct. It was the plate that was out. The tech used the wrong engine manual and the correct plate was not shown. With the Forums help, I got the correct manual and adjustment procedure. Thanks again.
Glad you got it. I don't use any manuals for any of these engines.
I just look at the way it's set up and how the throttle cable moves to figure out how it has to be adjusted or how it works in relation to the other parts.
Some of these have a plate that has a lot of adjustment sliding that's possible where others don't have any at all.
I always tell people to never mess with the governor especially never loosen the pinch clamp on the actual Governor arm because that's when people mess up their static adjustment.
 
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