Won't fire Craftsman 700 Series Briggs & Stratton Engine

I've got a Craftsman ROTArY LAWN MOWER 700 Series Briggs & Stratton Engine, Front wheel Propelled, 22" Multi-Cut, Model No. 917.370850.I actually bought this mower because the deck is solid and I have 2 6.75hp B&S that have rust bucket decks. Anyway, I starting taking the "new" motor down and draining the fuel because the previous owner did not know about non-ethanol. I ordered a new carb from Amazon, put it all back together and it started on one pull and I mowed the yard. When I tried to crank it the very next day I got nothing, including no fire at all. When I took the shrouds off the motor I could see lots of crap on the flywheel and on the contacts of the alternator (I see that the device I'm referring to as the alt in the parts list may be a misnomer. This mower does not have a battery, therefore, an alternator would not make sense. I think it is just the connector to the spark plug. Anyway, I used WD 40 and a soft copper brush and cleaned the gunk from the flywheel. I'm getting ready to run to the auto parts store to get a tube of gasket goo to make sure I can draw fuel without an oxygen leak. Any ideas I'd love to hear. I've maintained my own tools for over 50 years but this one has me befuddled; works well one day, nada the next. One other thing, I'd never heard of an air vane but this mower has one but the retention spring was gone. I scavenged a spring from another old mower. This user does not have permission to use the HTML BB code.

Check low oil sensor if equipped, and disconnect the ground lead from the coil and see if it fires.

Now I'm confused. I was about to bench the mower and thought to pull the cord. One pull, it runs. It's just a little bit rough but it runs. Just weird.

Oliver Douglas said:

Check low oil sensor if equipped, and disconnect the ground lead from the coil and see if it fires.

Click to expand...

The part you are talking about is probably the ignition coil, which provides the current to fire the plug. Trace the small wire from this coil to the shut off switch. Make sure when you pull back on the bail handle the shut off switch opens. If it doesn’t you have found what caused the no spark condition.