I have a jiffy as well mine has acted the same way and here is what I did to resolve the problem. 1) dump the gas out 2)using a hemostats check the fuel lines for hardness they should be flexible. If not replace them 3) replace spark plug with a high quality plug 4) mix new super unleaded with no ethanol!!! 5) test at home let it idle for 20 min rev it up a few times and repeat a few times just to add comfort.
If it starts and runs and does not get hot your good to go. If you have more problems and the cylinder walls look good then its the ignition coil and or carb rebuild time.
I can not stress enough the damage ethanol does to small engines in even one tank full. Good luck and stay on the top of the ice!!!