Sorry this reply took so long. While I was trying to type it, the system said the website was not available, then I ran off to do evening chores, dinner, etc. I shall add the newer quotes to this post.
I would replace plug first.
I would do that, but the nearest place to buy one is 75 miles from here, so I figured cleaning it would at least tell me if that was the problem. It did not solve anything. It
is making a reasonably good spark, however.
Only thing I can tell ya is sumpthin ya already know........that sucks!
Yup, it sure does. Seems everything I own dies the day after the warranty expires.
I wonder if it has something to do with the very cold winters here. I had a cheap piece of crap Walmart mower back in Orygun that I literally abused the hell out of, but it always started and ran fine, even when I accidentally mowed lava rocks. One year after moving here, it took its final breath and never started again. So I bought a new one and it started nickle-diming me to death in a year (finally died after three). So I bought a Craftsman with a two year warranty and it died after one, so they replaced it free. That new one died after one more year (valves seem to be stuck open - or so my compression tester said), so I got this TroyBilt (excellent reputation, but now made in China) and now it has turned out to be a piece of crap.
I am NOT a small engine mechanic, so all I can do is read the manuals and follow their destructions, which, sadly, don't tell me anything usable at all.
What engine is it on your mower?
It says TroyBilt 420cc, although it looks an awful lot like a Briggs & Stratton. Single cylinder carburated with a big sticker that claims is is ethenol compatible up to 10% (yeah, right - that crap dissolves rubber tubing).
Othwise crud in carb most likely.
That was the first thing I checked because the rough running and popping sounds seemed like a fuel issue. I did
not take the carb apart, but an inspection of the input port suggest no gummyness. If I were so inclined to disassemble the darn thing,
then I could comment about the needle valves. The fuel filter does not appear to be clogged.
Fuel stabilizers: Never used any. I figured Stabil was an expensive rip off. My method is that when I am done with a piece of equipment for the season, the fuel is siphoned out and the engine run until it dies due to lack of fuel. No equipment is allowed to sit through a winter here with gas in it if it is not going to be used. All the siphoned fuel is then poured into something that is still in use. For small engine equipment (lawn mowers, tillers, weed eaters, chain saws), I buy regular unleaded (Murphy's sells it without ethanol) and I add some octane booster to bring it up to a minimum of 98-100