I have a 60" Swisher trail finish mower that I installed a Briggs Intek 21hp engine on. Briggs Model #331977-0001-G1 made in 2012. When I'm on a steep incline it will sputter and shut down. If I go to a relatively flat area it will re-start and run fine until I hit another steep hill. Otherwise it runs great. I used to have this problem on the old engine (older I/C) and putting the oil slightly over the full line fixed the problem. Does this Intek engine have a low oil shutoff? I looked hard all around the engine and I dont see a sensor. If its not a low oil shutdown then how about the float design in the carb? I am researching EFI setups and aftermarket carbs, but I'd like to know your thoughts.