Kohler propane genset won't stay running

Hold the Red Button for much longer than you think. It has to fully heat the thermocouple safety device. Then release VERY slowly. There are tips here

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depends on your climate if genset runs in colder weather run the 14 if not then it's the 12

Sounds like the button is bad. Try replacing it

Check kohlerpower.com

Check the oil pressure switch, and oil level first. Then check rotor brushes and rotor slip rings may need polishing. If the problem is still there check stator and rotor windings

Is there a fault?? All UL listed generators including Kohler are required to lockout on a fault on shut down. This really sounds like a problem with your 2-wire auto start connection between your automatic transfer switch and genset. RDT model automatic transfer switch it is the 2 middle wires on the green connector and terminals 3&4 in the generator. close to run and open to shut down. Any open at any time will cause the unit to shut down. The 12 will shut down instantly upon an open because your 5 minute cool down is built into the transfer switch.

Check the genset controller for a fault, low oil psi, no output voltage, overspeed, overcrank / no crank disconnect signal / starter staying engaged, high engine temp.

is the sensor for the thermocouple located in the right spot in the flame,remove it and if you have access to a propane torch,heat the end till its red hot and leave it connected to the gas valve,then start the unit and this will tell you if the sensor is properly positioned in the pilot flame on the unit itself,if not you could have a defective new thermocouple or another safety device keeping it from staying lit or the gas valve is faulty

Can't search for a manual without model, type, serial, etc numbers...

A few things to take a look at:

1) Oil level / pressure sending unit. This is normally bypassed as long as the start switch is pressed. When engine starts, and switch is released, engine will die if sending unit is defective, or you are low on oil.

2) Exhaust temperature sensors. Older units were notorious for burning these up.

3) Cooling Water Temperature sensor. These cause trouble often, but mostly due to water pump impeller being eaten away by galvanic action and not able to pump water as effecively. End result is water temp higher than normal, which trips the switch, which kills the engine.

4) Alternator (generator) output not as it should. If output doesn't rise to proper level within a few seconds of engine start, the engine will be shut down.

5) Choke not working as it should

6) Bad fuel, bad fuel pump, clogged fuel filter.