I have an Intek 8.5 Horizontal 121237 0135 B1 that just died. I checked for spark, no spark I replaced the magneto 796964 and it started first pull and ran 10-12 minutes and dies, no spark. Checked using my spark tester, nothing, check by grabbing the lead, nothing. Let it sit over night and it started first thing and ran 10-13 minutes and died again, It wont start the rest of the day. Next day I plugged my spark tester inline and it showed spark like crazy and the motor fired right up. I turned it off and removed the tester and fired it up again and it ran 10-12 minutes and dies. Shot some starting fluid in it just to make sure it wasn't fuel and not even one pop. Checked to make sure the magneto was installed correctly and the small ground wire is on the bottom and the arrows are pointed correctly. Oil is full, it doesn't seem hot. When I changed the magneto I blew all the grass clippings and stuff around it so it is clean and getting air. New Air filter. It starts on half a pull, It has electric start but I never use it as it starts so easy on a pull. Any ideas what to change next?