I have a Gravely 44 inch zero turn, and I've had it since 2010, but is almost like new....long story short, it has about 72 hours on it. I had let it sit during the winter, and when I tried to start it back up it took almost a half hour before it got going well....along the way it put out alot of black smoke. I had just changed the oil, but I think I put the transmission oil in by mistake. So I changed out the oil and put in 2 quarts of 10W30 like the dip stick said to. It ran fine two or three times, but then I started it up again about 4 days later and it did the same thing....it takes for ever to get it going at full power, and it puts out black smoke. Then I shut it off and restarted and it back fired. Restarted it one more time and it once again was barely running and started smoking...any advice? Is it smoking because it is getting over fueled? If so, what is the remedy? Any help is appreciated. It had some old gas in it, but it has had quite a bit of new gas put into it also.
Black smoke means too much gas. I would almost bet that the choke is sticking closed. You don't say which engine you have. Briggs engines have a plastic choke shaft that has a tendency to warp causing choke sticking.
