Start? - Did it crank if eStart? Does it do anything … poop, fart, sneeze or anything? Some of those 4-S models are carb’d models, where if flooded … to ‘clear’ them you put them as fast as you can in neutral and then start it.
If carb’d, they are notorious for having the jets get clogged up due to fuel issues, even when running clean fuel. There are some good YouTube videos on how to remove the carb and clean the jet.
Maybe you will get lucky, but at my boat club, on 1 Club skiff & 1 owned by a member, we eventually replaced the carbs just to get those engines running reliably again. Unbelievable! But yet they ran after the carb replacement, go figure … who knows, maybe there was a bad batch of carbs???
On one of them they tried everything, their Dealer allegedly tried everything, and then I tried my hand at it … and while I got it running, it still wasn’t perfect. I hate to say it, but that 9.9 & 15hp carb’d models were almost the biggest dogs of a motor as I’ve ever worked on, almost rivaling Force motors with their weak/poor power packs.
Smell? - Have never experienced that, as that smell I believe you are referring to came from catalytic converters, but there’s no cats on small OBs, or any that I know of.