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Hello All, I picked up a Scotts Sabre by Deere 1752 with a Kohler Command 17.5hp single on it. Numbers are in the attachments. The governor went bad on the previous owner and he had it disabled by rotating the governor shaft CW and adjusting the throttle plate assembly. I replaced the broken governor gear and pawl and adjusted the arm fully CCW with the throttle being held wide open. The engine has always run very smooth and easy to start. Just no balls when under load.

At this point I have the max rpm at 3500 and min at 1400. The engines starts and runs smooth, but it SLOWLY BUILDS to speed and there is no governor activity even on cold days. When put to idle then increased quickly, the speeds up slowly. The governor spring was in the top most hole, I moved it to the middle and no effect. I can push the arm more CCW as the engine is at max speed and it gains a few more rpm. Most of the engines I have worked on will surged slightly until warmed up. Not this one. It does not bog down when the manual PTO is engaged. Can't test in high grass as there is none.

The throttle cable is adjusted so it opens the butterfly fully and the max RPM was adjusted with the whole throttle assembly plate. The service manual shows the procedure to adjust the is plate. It shows two styles, neither of which is this one. I think I'm close.

Thanks for the help,

If that is the throttle cable going up and then back down in the 3rd picture how tight of a bend it that cable making. Could be the cable isn't moving freely and slowly crawls through the conduit to increase the throttle instead of moving quickly when the throttle control is moved.

No, that's the PTO cable. Thanks for responding

Probably time to stop, take a nap, and start over, starting with the static governor setup. Looking at your picture the speed control bracket looks like the figure 5-24 on page 5-15 of the service manual. I would redo the setup procedure starting on page 5-13.

OK, will do.

I would add, “Don’t say to yourself I did it like this before “. Say, “I know how to do this, does the manual say l’m dumb and should do it this way”. If a customer came to me with this problem, I would say “don’t tell me what you did, let me figure it out from scratch “. When I get a problem and can’t figure out what I did wrong, I sleep on it and then start over like I’ve never touched it yet.

Got it, thanks

Hey Rivets, I'm gonna adjust that bracket later today. Another issue with this engine is if I adjust the idle speed lower than about 1500 rpm, it runs very rich and blows black exhaust. Anything above that speed and it runs smooth and clean.

Well Rivets, you were spot on again. The tech used the 590 manual which is similar, but didn't show the correct bracket. Everything works well, including the governor, but the max rpm I get is 3900. Low is at 1400 rpm and no lean condition. Plate is adjusted all the way up. I messed with different cable positions and nothing helped. I'm hoping this will be enough for hydro and blades. Moving the governor spring lowest hole causes surging. Middle position it is.

If you have a way to increase the rpm's let me know, otherwise thanks for all your assistance.

You are already way above spec'd max rpm if you are at 3900 rpm. Slow her top speed down.

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.

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.

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.

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.

Freddie21 said:

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.

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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.

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

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

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.

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.

Freddie21 said:

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.

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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.

I agree, but I have heard on this forum to adjust the static adj any time a carb is replaced. I don't do that or any other time. This one had previously been adjusted to overcome replacing the gear.

Freddie21 said:

I agree, but I have heard on this forum to adjust the static adj any time a carb is replaced. I don't do that or any other time. This one had previously been adjusted to overcome replacing the gear.

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So if they adjusted it because the inside Governor had grenaded and had no Governor action and they were trying to compensate, they should have stopped right there because that is definitely not a proper way to operate an engine and a pain in the butt to try to operate it by a throttle control by hand.
I never do a static governor adjustment just because I've had the carb off and reinstalled it or replaced it with a new one because it's just not necessary 98% plus of the time.
I know there is a good number of people in this form and others who have this kind of what I will call a mental hang up to do things 100% correctly or "right".
I simply don't have time for that because even if I didn't do this commercially, which I do, I still have lots of other projects of my own so if I was fixing my own mower I'm going to slap the carb back on it, or in my case I'm never going to remove the carb in the first place to clean it out because that's simply faster, and then I'm going to move on to the next task. Lol
I don't have time nor am I going to take the time to do the extra steps that are highly unlikely to be needed in the first place..
Other people somehow seem to sleep better at night if they "go the extra mile".
I do not.

From what I understand, a local fix-it shop made whatever adjustments to get it to run. It did run well, just had no balls when it needed. They wide open throttle cable was the issue with the plate. The choke screw had to be backed off to get the two holes to line up.