Bad gas. I have heard the excuse "bad gas" over the years and I always thought that it was just an excuse for being a poor mechanic. I have kept gas in my garage for years and still used it. I had a 1964 impala that fired right up with 5+ year old gas. This year, I put gas in my Mower and it wouldn't start. I got another mower that had always started first pull. It hadn't been started this year but it still started on the second or third pull. Once the gas ran out I put the gas in it from last year. It would not start either. I now had two mowers down. I drained the gas from both and filled them with new gas. Miraculously, they both started. I think something in the gas has changed. My neighbor has noticed the same thing. He is actually a mechanic and he is the one that informed me that something must have changed in the gas. I just decided to change the spark plugs on both mowers. there was a white sludge in the cylinder of the one that hasn't been used. I think I'll just use this old gas to start fires or something. Guess we can't keep old gas anymore. Hope this helps.
Fresh gas did help it some but I think it is also has a clogged line. Mowers are now all California compliant which means they don't work as good. lol There's very little if any leeway if your carb gets clogged or the filter gets blocked. It's a pain not being able to store gasoline for my mower. I might go down to half a gallon in storage at a time.
Yeah. The California compliant thing makes sense. I have always started up until this year. The one mower is pretty old though so I'm not sure that is the problem. guess I just won't store gas anymore. I'll dump it in my car to mix with the new gas or use it for a bonfire or something