Follow-up to this posting.... noticed that in Tecumseh Engine Operator's Manual that their engine Warrenty is limited for 2 years. I missed that window by about 6 weeks! Oh well....had better luck with an Honda HR214....with a Honda engine. Lasted 14 years befor the mower wore out.

Very strange. Was this mower used commercially? Sounds like it must have had a tremendous number of hours usage. Were you using regular or premium grade fuel? Premium, i.e., high octane fuel, has been known to cause carbon build-up in engines not designed for it.

Resident use only.

Regular gas with an 0z of Sta-Bil for fuel.

About 12,000 feet of grass.

Pennzoil 10-30....at least twice a year.

Used 2 other mowers, a Toro made in 1990 and a 42" tractor. when wanted to mow faster or didn't need the walkin exercise (my age is 71). Used only 87 octane, added a ounce of Sta-Bil to 2 gallons most all the time.
xlindax, can scan you pictures if you want.

Answers that other post I guess that keeps floating around about "Are Honda engines worth more than a Tecumseh?"

After telling some gal about this I am coming to the conclusion that I should have bought from from any Toro Authorized or Master Service Dealer. Home Depot is not a Dealer, HD is only a seller or retailer. So naturally they farm out the under so called warrenty work to an unauthorized repair servce shop. Buyer Beware.

This is extremely odd, particularly with the use of STA-BIL which contains fuel system cleaners. I'd say there was some fault with the engine in some way, making it run rich or perhaps burn oil. Wait...10W30? The manual should require SAE 30. Maybe it was burning a little oil with the multi-grade. Recently I got a mower running for my sister-in-law (I had bought it new in '89 and given it to them a few years ago). It had been run with bad gas - real bad, 7 or 8 years old, then left to sit for two years. It was terribly carboned-up and the oil was like tar. When I pulled the plug, two hunks of carbon fell out. All I did was remove the oil and gas, put a new plug in and replace the fluids. The thing ran perfectly. I cleaned it up and took it back. The point is, I don't believe the story about the carbon destroying the engine. In order for this to be true, the engine would have gradually lost compression as it burned more and more oil (with blue/white smoke), finally getting too weak to run. But this is not a sudden thing and it would start smoking long before the end. Also, the oil would get black after only an hour or two of use. Since your mower ran fine one day but wouldn't start the next, I suspect a clogged jet in the carburetor. I hope you still have the mower. BTW, it requires complete engine disassembly to make the diagnosis they gave you, and the engine is basically not worth the labor to do that. I doubt they tore down the engine to examine the piston and cylinder.

I agree with Saxman. The so called mechanics either did something to ruin your engine, or gave it a "wall job", a term used by auto mechanics at dealer shops! Thats where they set your car beside the garage wall and ignore it! Either because they aren't smart enough to find the trouble, or because they think you must be "on" something, because they haven't been able to find the problem, nor repair it! I never heard of carbon breaking loose and scoring the cylinder wall, or the piston! Especially in an engine as new as yours! Carbon build-up on a cylinder head will sometimes cause pre-ignition, but i have never come across that condition in lawn mower engines
No, i think they did something to your engine, and to get out of the fix they were in, told you that "Cock and Bull" story to absolve themselves of any blame!
A thought comes to mind: Maybe they inadvertantly dropped a small screw into the spark plug hole, and not wanting to tear it all apart again, on shop time, they just started it up, and it took care of the problem with a big "bang"! I have seen that happen with auto engines, where the mechanic laid some bolts, or nuts, near the open engine, didn't notice they had fallen into a cylinder, then put everything back together, and started the engine---only to say:"What's that knocking noise"?

I honestly dont believe they (HD) are going to give your mower to an unauthorized repair store. Who would be paying for the repairs had the engine failed under normal conditions? Those dealers make money off of people like us and love it. I think I would get a second opinion from another shop. The worst that will happen is it cost you $25.00 but it could save you $438.00