Snapper Rear Engine Rider Dies when I let the clutch out

I have a 30" Snapper rear-engine rider with 18 hp engine I bought new about 3-4 years ago.
It's got a strange problem I can't get a handle on.
When I start it up I take it off choke and adjust the throttle until it runs smooth. Then when I put it in gear and release the clutch it dies unless I put the clutch back in.
My first impulse is that it's a choke/choke-related problem. And it may be. But when it starts to die, it's very abrupt; like an electrical problem. It's like one of the safety cutouts has be activated.
Any agreement that it may be electrical and have diagnosis suggestions or should I just I just look at it as a choke(ing) problem and some diagnosis problems on that.
Thanks from a newby,
Lawrence Perry

Check your operators manual for clutch adjustment procedure.

:welcome:

You have a problem in the safey circuit.
The mower thinks ( as far as a mower can think ) that you have fallen off so it shuts down cause dosent want to run over you.
The seat switch is connected to the brake switch and the magneto kill wire.
Somewhere the circuit is completed to ground and the engine stops.

Two good ideas. I'll check 'em out.
Thanks,
Lawrence

Or perhaps failure of carb to provide enrichment to sustain loaded engine? Float level , sticky inlet valve, or partially plugged main jet?