I have a kohler CH23-76591. When the mower came to me it wasnt running. I cleaned the carb, replaced all fuel lines and fuel pump and got it running. I then found i had spark on one cylinder only. Because it was in a Grasshopper 223 zero turn mower and you have to pull the motor to get the shroud off, i decided to replace both coils and now have good spark on both cylinders. I pulled the carb off again and cleaned it again. Checked the compression on both cylinders (120psi on both). I checked to make sure the fuel solonoid wasnt loosing current during pto engagement and that it wasnt excessive load from mower deck. I found that if I move the choke to half on the pto will engage without the engine dying. Im not sure what to look for now. I forgot to add that i did a complete service with new air filters and spark plugs. i even put another set of spark plugs in to make sure they were good. Thanks in advance for any help.