My Kohler Command 25 hp now runs WOT on its own

Bleach

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I got the head back yesterday and got it all back together today. It all started fine and idled good for a few minutes but when I increased the rpm's it all of the sudden went wide open throttle and I couldn't get it slow down. I had to choke it to slow it down. I checked the governor linkage and I have it set correctly. The carb throttle keeps opening up if I don't hold the linkage. If I take the small spring off the throttle link and lever it will idle normally but will surge if I increase the rpms. I've tried different holes on the governor lever and it goes WOT every time if I keep the spring attached to the throttle link and lever. For whatever reason the spring keeps it from closing. I'm thinking something might have happened to the governor.

I was reading around the site and came across a thread where some mentioned a clock spring on the carb on a different engine. This could solve my throttle problem but I didn't see any clock spring on my carb. I need to try to find one that would fit. I'm sure one would have enough tension to keep the throttle from opening up on its own.
In the meantime my grass keeps growing.
 

bertsmobile1

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The governor is not working.
Throttle opens up
Governor closes down
Most likely bob weights dropped off when you put it back together
 

Bleach

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What are the bob weights you mention? I put everything back I took off and there were no left over parts.
 

reynoldston

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I would start by readjusting the governor other then that you have something hooked up wrong. I have no idea or ever heard of a clock spring?? Just what model command do you have? Also never heard of bob weights? unless berts is talking about the internal governor weights and just changing the head doesn't effect them?? as far as any Kohler heads I have ever changed..
 

Bleach

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I have a CV25 in a 1997 Craftsman 50" mower. I have the Kohler manual for it. I tried adjusting the governor every possible way. The problem I seem to have is the throttle wants to stay open. I can close it and it operates freely. The governor shaft turns about an 1/8th of turn or so. I can't imagine what could have happened to it while I was R&R the head an related components. It seems as the governor isn't doing anything as the rpms are going higher I could ever imagine this engine could produce. Once it revs nothing brings the revs down other than choking it and shutting it off.
 

reynoldston

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When the engine isn't running and the throttle is wide open the carburetor throttle plate will be wide open. Then when you start the engine the governor brings it down to operating speeds. You should have two adjustments wide open throttle 3600 RPM's and idle speed 1200 RPM's. You will need a portable tack to make these adjustments. If you made all the right external adjustments and the governor still doesn't work then I would think it is a internal problem. You tube will show you how a governor works if you need help with that.
 

Bleach

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I don't think the governor is doing anything on start up. I'll have to see how the governor is supposed to function on the videos. If it is internal then I doubt I will bother fixing it. I've thought out a few ways to run the the throttle bypassing the governor. I think I can run it without destroying the engine because I've often adjusting engine speed when mowing. Some areas need more speed, some less. That's worked well for me.
 

reynoldston

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1. Make sure throttle linkage is connected to governor arm and throttle lever on carburetor. 2. Loosen nut holding governor lever to cross shaft. 3. Move governor lever toward carburetor as far as it will go (wide open throttle) and hold in this position. 4. Insert a long thin rod or tool into hole on cross shaft and rotate shaft clockwise (viewed from end) as far as it will turn, then torque nut to 6.8 N·m (60 in. lb.)

Do this as per service manual? After doing this if the governor doesn't work you have a internal problem.
 

Bleach

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Yep I did that. I had it set that way before I started it. I'm not sure I want to tear into it. If it's s simple as pulling the engine and unbolting the lower case to get at the governor, maybe. I looked at the book and it doesn't illustrate the governor more than showing the gear in the pan and the cross shaft. I didn't get a good impression how it goes together by the book.
 
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