Old thread but thought I would post on this anyway. Being certified through John Deere and Stihl on small engines, they both recommend using brake cleaner over carb cleaner in the can. Best I understand the spray carb cleaner has some chemical in it that will damage some of the carbs now days. Preferred method of cleaning is with an ultrasonic cleaner with a carb cleaner solution. I use an ultrasonic cleaner regularly on small engine carbs and man what a miracle it does. If anyone is interested in getting one for a shop Id suggest a Sharpertek brand. The models with the water heaters do work better.