I got Tom Sawyer'd by a cousin, he ran his mower low on oil and exposed a piston. he paid a "guy" to fix it. this is the engine he put in it.
ran good but a WOT. developed an issue that flooded the crank with fuel, I have studied the posts and suspect it is a bad gasket 698781. carb is 697722, G02401 4X28 pretty sure the gasket will fix that.
BUT, the throttle is WOT, the gov is pulling WOT, I can force the gov spring and close throttle to idle stop and it purrs like a kitten, a raspy kitten but still idles(figure gasket making it a lil rich). I have pictures and such, even a video. but I do not know how to adj Governor and I really would rather not! but I cant figure out why it is pulling the throttle WOT
Could be that gasket but don't overlook the float valve 698537 and be careful and don't drop the jet out of the white plastic emulsion tube. They like to fall out when the white part is turned upside down, and people don't realize it is missing until it floods at full throttle.
The governor spring is supposed to pull the throttle to wide open. The governor gear through its mechanical components is suppose to close the throttle. Move the throttle from idle to wide openand observe which direction the governor rod turns were it enters the engine crankcase. Then loosen the bolt that holds the arm attached to the rod, and while holding holding the throttle at wide open throttle turn the governor shaft in the direction in the same direction as it turned when moving from idle to full throttle and then tighten the nut back down on the governer arm to lock it into place. Need to be quite snug so it doesn't slip.
I submitted a reply yesterday and this slow site did not let me post my reply.
One more time. Site is erratic speed, etc.
Does the engine run at WOT or are you just seeing WOT with the engine not running?
WOT with the engine not running can be a normal thing is why I ask.
Here is a link that might fit your carb repair.
If gasket in the top of the carb on pic 7 is bad the carb will leak fuel into the bowl and act like a leaking needle seat. this gasket stops the gas BEFORE the needle seat. I use a low pressure pump and invert the carb and test at 5psi for the inlet pipe barb to seal. sawzilla.com has lots of Nikki parts reasonably priced. https://outdoorpowerinfo.com/repairs/briggs_intek_single_ohv_nikki_carb.asp