IMHO changing the oil on an hour basis regardless of how it "looks" is important. The OEM does not come up with these hourly change numbers by using a dartboard. Keep in mind with 20/20 vision you cannot see particles less than 40um (contrasting no less) without magnification. Even on units with an oil filter, they are rated at 20 or 25um and particles less than that size cruise through the filter unless they get hung up as the filter clogs. Worse, oddly shaped particles say 15um wide, and 35um long (like a spear) can pass through a 25-20um filter. Changing the oil (when warm after the particles have been stirred up into suspension) is the only way to rid the engine of them other than flushing the case. These small particles crash into parts and make more small particles, or some larger ones too, and the cycle only ends the day the engine stops running for good. Keeping the oil changed at the recommended interval rids the case of the majority of the particle population so you have fewer projectiles in there with fresh oil. In hydraulic systems we deal with this another way as it would be impractical to drain a 1,500 gallon industrial reservoir on a regular basis. The use of 10um, 5um, or 2um filters (incidentally a 10um filter would remove all the red blood cells in your blood, and a 5um would strip the white cells out leaving you only with plasma, so these are FINE filters and not the one on a Briggs engine.) and occasional external purification by use of a purifier unit keeps the oil dry (water removal) and clean. Since it would be impractical for the average homeowner to own an oil purification unit (the good ones start at $22k) and reprocess the used oil with new additives, changing it regularly is the best line of defense. After a season (25 hours) I am sure there is more than 300ppm of water in the oil, not to mention gas too.

Saxman is absolutely correct. I bought the self propelled version with the 190 engine. At first blush, it looked like a steal. What became evident after about three hours use was that the mower was a good idea poorly executed. The pluses to me were the honda engine and the stainless deck. The minuses were that the deck had not so subtle flexing action over rough terrain, the wheels wobbled, the control cables were held in place with the zip ties and the S T U P I D auto return choke needed a helping hand to close. Back to Costco it went.

Ray, It sounds like you've probably covered all the bases except for buying the new parts or a new carb, but just a couple of more thoughts to throw out. As I said you've likely done this, but if not, have you made sure the gas tank screen is unclogged? And this is silly perhaps, but if you could stomach taking the carb apart again without rebuilding it, and under the assumption that the float valve is sticking, you could mount the needle in an electric drill and with very fine wet/dry silicone-carbide paper (600 grit or finer maybe), gently reshape the rubber tip so that it has an ever so slightly more blunt profile. If you think about it, if the tip develops a sharper angle than the valve seat, it will tend to stick in the hole at the end of the cone shaped seat, like a cork in a bottle. But if the tip is the same shape as the seat, or slightly more blunt, the elastic forces that develop in the tip will tend to push it off the seat, rather than anchoring it there. I've never tried this, but if you're going to buy new parts anyway, and have the time... Jim

sounds like the deck safety switch. my old mtd 600 had one. yours might not have one being a craftsman, but it is worth checking. follow the deck raising/lowering handle down to where it hooks up under the frame, try to find an electric switch that is spring loaded, it will look like a pushbutton, and is designed to push shut when the deck is raised all the way up. yours might be sticking closed or not opening all the way,or not making good contact. sometimes the mechanism that holds it in place gets bent from pulling up on the raise/lower handle too hard.