I was mowing the lawn today with our MTD garden tractor when it suddenly and without warning started sputtering and died. The engine is a 14.5 HP Briggs & Stratton OHV job with electric start.
I checked for obvious stuff like clogged fuel and air filters, and cleaned the spark plug (it had some carbon deposits). Still no good, the engine barely catches even with the throttle wide open, backfires through the carb, and dies. On a car I'd say it sounded like it was trying to run with severely retarded ignition timing, or too lean a mixture, but I'm not quite sure what to test on this thing. (This is a 1996-vintage mower, so I'm pretty sure it has transistorized ignition, not points.) Maybe some dirt got past the fuel filter into the carb? Any "gotchas" to be aware of in taking the carb apart?
Any pointers on what to check, or to troubleshooting/tech info online would be greatly appreciated!