Normally you would look at the old blade, get a number from it and order it online. Since the mower is a Troy-Bilt and was used when you got it, it may not have had the original blade. I made a mistake above - somehow I got it in my head that it was a Toro. You'll have to get the model number off the mower and look up a blade at one of the on-line vendors. Your mower was actually made by the MTD Corp. which owns that brand along with many others. Their site may be of some help in researching the blade. Now. With all that, the new blade you bought should still work. The main thing is to find out if its on right. If the starter pull cord comes off the right-hand side of the engine, the blade is said to turn 'clockwise'. When you pick up one side of the mower to work on it, keep this in mind, as it will be 'counter-clockwise' from underneath. BTW, always pick up the side with the air filter to keep oil from running into the intake tract. Disconnect the spark plug any time you put your hands under the deck to raise it up. Look at the blade and see if the sharp edge is pointing in the direction of rotation and the airfoil on the top of each blade end is 'up' toward the engine. Now check the blade for proper tightness - put the wrench on it while you block it at the bottom with a piece of wood under your foot. Look at the ends of the blade and see how close they are to the inside of the deck - should be about 1/4" clearance. The old blade was a mulching blade if it was the original, because you have a mulching mower. I still have not figured out why the self-propel went out at the same time as the blade change.

One of the frustrating things about lawns and water is that sometimes a lawn that looks like it is dying because it doesn't have enough water may be dying because it is drowning. I think there's a good chance that your problem is due to too much water. I live in the desert and I watered for the first time yesterday. We did have almost three inches of rain in June this year, but it sounds like you've had lots of rain, also. The areas that are affected may have poorer drainage or may be a little lower so that water sits there longer or they may just have some grass that is more susceptible to fungus. Don't water until the grass starts to get stressed, then water deeply. You need to let the soil dry out down to about 4 inches or so. If you can't tell by the grass, use a screwdriver and poke it into the ground to see how deep it's moist. I'm pretty sure at least one of those pictures shows some KBG, so if those areas have died, there's enough grass around them that is still green to fill in. I would not fertilize now, except maybe with a slow release fertilizer. Most organic fertilizers are slow release and there are some synthetic products that are also slow release. I don't have a lot of direct experience with fungus (it's just not a problem when the relative humidity usually hovers around 5%). I've read posts from others who have used cornmeal at 10-20 lbs per 1000 sq ft and had good results from it. That would also qualify as a slow release mild fertilizer. There are also synthetic anti fungal products available. I think the synthetic products are faster working. One important point is that you should not mix the two approaches. The cornmeal works by encouraging the growth of beneficial fungi, so if you use an anti-fungal application of some sort, the cornmeal won't work.

Thank you for doing some reading. You don't really need a diagnosis before using corn meal. It doubles as an organic fertilizer as well as eradicating most lawn diseases. Since it stopped raining for a week I put some down today. So your lawn service treated for grubs multiple times already? I think I know the answer to this but did they look for grubs before treating? They're easy to find. You dig up a square foot of turf and if you find fewer than a dozen grubs, you cover it back up and leave everything alone. If you find a slimy, uncountable mess of grubs, then you can take action. But you might wait another couple weeks to go looking for them. This time of year they would still be eggs. Then you would expect to see damaged turf in August or September, not May and June. You may need to adjust your sprinklers, too. If you are watering more frequently than once every 5 days (in 100 degree heat), then that is too frequently. Grass should be watered deeply and infrequently. I have yet to water my lawn either in San Antonio or in the Hill Country. Deeply means 1 inch all at one time. Infrequently means once per week with temps in the 90s, once every 2 weeks with temps in the 80s, once every 3 weeks with temps in the 70s, and once a month the rest of the cooler part of the year. With temps in the 100s you should be able to go once every 5 days. When you allow the soil surface to completely dry out you avoid disease and weeds in St Augustine. Lawn care is as simple as watering (described above), mulch mowing at the highest setting (always for St Augustine), and fertilizing 3x per year. If you are doing those three things you should not need any other treatments like insecticide, herbicide, fungicide, dethatching, core aerating, top dressing, or composting. Once you eliminate the need for the counter measures, it's dead simple.

Thanks, I thought so but needed someone else's opinion, since it is so sandy and dry there