Small Engines (Lawn Mowers, etc.): Snowblower, white lithium grease, toggle switch

Question
My 3.5 HP B & S snowblower has a plastic key to open the contacts when pull starting unit. After an hour or so the contacts freeze up and I have to bury the auger in about 2 FT of snow to shut it off. When I pull out the key the unit keeps running. Can I install a toggle switch to by-pass the present plastic key set-up. And if so, how do you wire it in with seemingly only one wire coming from the starter. I can't believe that I am having a hassle with such a simple task. Hopefully your experts can help me.  Thankyou!

Answer
My recommendation is spray the contacts with white lithium grease (or some thick lubricant that will stay in place) to prevent condensation and ice build-up.  There is only one wire because the switch connects to ground via the housing it's mounted on.  Hope this helps.