Chosen Solution
Ok. I have a 5hp Briggs & Stratton on my MTD rototiller. I’ve changed the carb gasket, see picture. I’ve cleaned out the passages. I’ve used sea foam in the fuel, it’s got fairly new gas. I cleaned and checked the gap in the spark plug and it’s good. I can still see through the air filter. But I can start it and it’ll run for a few minutes then die. After the sea foam trick if I babied it I was able to do a little bit of rototilling, but then it died and wouldn’t restart no matter where I positioned the choke lever. What else could it be?
@actimm check for spark first. remove the plug and hold it against ground i.e. cylinder etc. and see if you have a spark. If you do not have a spark you know it is related to either a bad air gap on coil .010 inch or a bad coil. If you do have a spark check for fuel supply. See if it does start when you pour a bit of fuel directly into the carburetor or use some starting fluid and see if it starts. If it does you know that the issue is with the fuel supply. Check to make sure that you do not have a vapor lock, kinked fuel line etc. Most common issue with the small engine is a stuck float in the fuel bowl. If it is stuck you carb will not get the fuel it needs to run your engine. Let us know what you find.
After reading above answer one other thing to try is to loosen fuel cap. If it starts and runs replace fuel cap since it was not venting correctly.
