Dull Blade
Frequent use of the Jiffy Auger results in a dulling of the cutting blade. You may prolong the useful life of the cutting edges by drying the blade after each use and also rubbing a thin film of oil onto the blade before storing the device. If you determine that the blade needs sharpening, carefully remove it from the auger and take the blade to a Jiffy authorized service facility---usually the retailer where you bought it---and have it sharpened.
Sputters While Cutting
Jiffy Ice Augers require a specialized mix of high octane unleaded gasoline and synthetic two-cycle oil. If your auger sputters while cutting and perhaps even stops suddenly, empty the gasoline tank and discard the mixture you have prepared. Purchase a one gallon gasoline can and fill it with one gallon of high octane gas. Add 3.2 ounces of two cycle oil---Jiffy manufactures a blend that contains a fuel stabilizer---and mix. Use this mixture for the entire season. Discard any remaining mix, as well as the content of the auger's gasoline tank, at the end of the ice fishing season. Be sure to start each season with a fresh mix of gasoline and oil.
Auger Runs Rough
Remember that the Jiffy Ice Auger will not run as smoothly as a car engine; however, if it runs so rough that it makes operation virtually impossible, turn off the engine. Check the spark plug and ensure that the spark plug wire has not come loose; you may need to clean the area to remove debris. Ensure that the fuel tank's air vent screw is open. Make certain that the cutting blade is fully inserted into the machine, and that the locks holding it in place are snapped shut. Once you verify that all these conditions are met, turn your auger back on.
Engine Trouble
Unless you have had the auger for quite a while and your warranty has run out, do not attempt to fix the engine or adjust the carburetor yourself. Tampering with the engine or carburetor voids your warranty. Contact the manufacturer---you can find contact information on Jiffy's website---and locate a nearby service center to have it serviced.