I decided to use my 16" Craftsman chain saw and as it had been sitting idle for about a year I put in a ounce or two (this is a lot considering the size of the gas tank) into the 1/2 full gas/oil tank. I then filled the tank with fresh gas/oil (not synthetic). It took a few puls to get it started, but it did start and ran rather well, except it put out a lot of visible smoke. Could that be due to a too rich mixture of Sea Foam?