cersbo........you do know enriched mixture by pumping yer spring loaded choke knob is eazier to sparkle with weak sparkies, don't you???
Our experience sez 15-mins is typical time fer weaksister ignition switch to cause weak sparkies and ruff running and stalling. After cool down of about 30-mins, ignition switch is good-to-go fer nutter 15-mins of eazy runnin'
Keep yer itchy-twitchy fingers off'n them handy-dandy carb tweek'ums. They ain't-chur problem.
BTW, about 1-mins of runtime and stalling out is BAD condenser. NOT yer problem.
About 5-mins of runtime is CLOGGED in-the-tank fuel filter. NOT yer problem.
It takes about 1-hr of running fer yer 1-terminal squarecan ignition coil to cause weak sparkies. NOT yer problem. As said, 15-mins of runtime is BAD weaksister ignition switch. Do I haffta tell you to replace it??? ........Dell, yer self-appointed sparkie-meister