Toro TimeMaster 30" shutting off

I have a Toro TimeMaster 30" mower with a B & S model 14D9320220F1 engine.  I have been experiencing occasional issues where the motor shut down.  I can generally restart it immediately or wait a minute or 2.  I would sometimes see gas leaking from around the gas cap.  After fighting this problem for several weeks I changed the coil, OEM part, set gap at .010 and the mower started right up.  I mowed the entire lawn and the mower never shut off.  The temperature that day was relatively cool.  Today the temperature is around 89 and I mowed for the second time since changing the coil.  I had mowed about half the backyard when the mower again started sputtering and shut off.  I noticed gas leaking from the cap.  I reseated the gas cap and started the mower.  I was making the final pass in the backyard when it shut off again.  I gassed up the mower, reset the cap and proceeded to the front lawn.  I mowed the entire from lawn without the mower shutting off or gas leaking.  Can all this be related to a bad gas cap gasket?  Any suggestion will be greatly appreciated.