This link should get you the Kohler CH service manual.

http://www.kohlerengines.com/onlinec..._690_06_EN.pdf

It will explain how to trouble shoot the engine and how to adjust the governor.

it will run a lot faster than 3800 rpm's but not for long that's why they govern them down so they don't explode...I'm not sure what the rpm spec. is on your motor but the k series singles is 3600 max.

I'd set it to run at 3800 RPM no load. It won't hurt it.

Thanks for all the advise everyone

I was able to adjust the governor somewhat and raise the no load rpm up to 4000 or so which I can reduce with throttle cable to 3600 approx.

this has helped a lot and I can now mow low medium grass fairly well

can you tell me how critical the torque setting is on the gov bolt are ?
I don't have a tq wrench and if I get it too tight it seems not to want to rotate

there still seems to be an issue with the pto, seems like if I hit tall grass the belts can slip allowing the blades to slow even as the engine maintains rpm

I have looked at the service manual operators manual and kohler manual and can not find anything on the pto and e-vac system.

anyone know of any info on parts breakdown and adjustments etc ?
I know the vac seems to fully retract when pto is engaged

the "new" pto belts I installed, I have to fess up that they were outside hanging on the shed fo maybe 2 years but they still seemed pretty much like new, hate to spend 50 if they are not the problem

4000 RPM is too fast. Slow it down. Risk scattering the flywheel at 4k

I had trouble adjusting the governor per the manual
it said the turn the cross shaft full clockwise. if I do that the rpm goes ballistic, had to back it off slightly. If I reduce anymore the rp, drops down to 3000 which is where I started.

so if I make sure that I reduce rpm with throttle will I be OK ??
I know I cant run it at 4000

the gov adjustment seems really sensitive

maybe I should add that I adjusted with the engine turned OFF, is that correct ?? If it were running and I moved the gov lever full throttle, the rpm would be way high

Your doing something wrong. You should open the throttle all the way, then rotate the shaft the same direction the lever moved. I don't recall if it's cw or ccw. Then, using the throttle stop, adjust max RPM. This really is very easy.

No, you cannot use the throttle as a means to control RPM. That would defeat the purpose of the governor. Besides, if it's not set right, it's still out of adjustment.... just now the other way. Low RPM won't be controlled correctly.

I looked at the service manual, on pg 28 it says to turn clockwise and use 65 in/lbs TQ and then on pg 81 it says to turn counter clockwise and use 60 in/lbs TQ

beats the heck outta me

I just now got it somewhere in the middle and its about 3500 right now.

but its really hot this afternoon and now the pto belt are totally slipping so tomorrow I'm going to get new ones at the dealer and see what happens

its seems like very little movement on the cross shaft anyway, maybe between 1/4 to 1/2 turn full left and right, does that sound about right ?