My machine is a Toro Titan MX6080 zero-turn mower with a 60” deck. It was included when I bought my property last winter, so I don’t know its history except that it was bought new in 2013 and was obviously poorly maintained thereafter; when I went to get it ready for use this spring I found that it had 180 hours on it, the oil was black sludge (probably never changed), the air filter was almost as black, the belts were notched and frayed, and the blades were not only dull but also bent and split. After I cleaned everything up it ran great for me for 20 hours or so before the problem first appeared.
The problem started a few weeks ago. I’d be about 30 minutes into my mowing session when the engine would suddenly start to wane and surge, especially but not exclusively when going through taller or wetter grass (i.e. heavier load on engine). If I just stopped mowing but left the mower blade running it would go RRRRR (normal speed)-rrrrr-RRRRR-rrrrr… maybe a dozen times before it would resume normal operation and I’d go on with my mowing until it happened again several minutes later. If I tried to keep mowing while it was having the issue it would stall out and I’d have to restart it. Once it started doing this it would do it more frequently thereafter until I was done with mowing for that day. It occurred to me to try loosening the gas cap when a bout of the waning and surging began but that didn't have any effect.
Then on a subsequent outing it got to the point where I would have to turn the mower blades off and sit and listen to the engine go RRRRR-rrrrr-RRRRR-rrrrr… maybe 20 times before it would smooth out and I could turn the mower blades back on and get back to mowing for several more minutes before it happened again. If I didn’t turn the mower blades off it would stall out.
More recently it got to the point where I would have to pull the choke a little ways out for a bit to smooth it out and keep it running, even if I turned the mower blades off right away. And it started happening so frequently that after about the first 20 minutes of mowing I’d spend nearly as much time sitting in place listening to the engine wane and surge as I did actually mowing.
Now, this morning, it started behaving this way more or less as soon as I started mowing (albeit some admittedly tall, wet grass), before the engine had even really warmed up. I think it’s now to point where the mower is essentially useless.
If I’m just traveling on the mower but don’t have the blade running (i.e. lightest possible load) it hasn’t shown the problem at all.
Yesterday I called the only repair shop anywhere near my modestly remote location. They said that they could arrange to come get it – I don’t know how quickly – and that after it arrived at their shop they’d “add it to the queue” – meaning it would be AT LEAST 2½ weeks after that point before they’d even look at it, and then of course they’d have to repair it and get it back to me at some point after that. I can’t imagine how long my grass would be by the time they got it back to me! And I have an awful lot of grass, literally several acres of it! And my wife’s family is coming soon to see our new home for the first time!
I’m game to tackle the problem myself, but I have very little mechanical knowledge (all self-taught and last used many years ago). All the repair shop told me was what I already figured. It has something to do with the fuel delivery system; they’d have to have it in hand to figure out exactly what. They talked about ethanol in fuel, and I do buy such gas, but the manual says that it’s OK and I add Mechanic-In-A-Bottle to every gallon, besides; they said ethanol can cause water problems, nonetheless. They said if there’s water in the carburetor then it will need to be taken apart (but if that’s the case then why would the problem come and go, and not affect the engine if the mowing blades aren’t being used?). They mentioned the fuel filter and at least one or two other things that went right by me. NONE of my mechanical experience has ever involved fuel delivery system issues; I’d probably recognize a carburetor if someone showed me one, but I’ve never done anything with one.
But if anyone can offer clear, detailed instructions on how I can diagnose and repair my machine, I’ll give it a go. At this point I really don’t know what else to do.
Sorry to make you read through all that, but I wanted to make sure I fully described the situation. Thanks for your time, in any event!
Gerry
The problem started a few weeks ago. I’d be about 30 minutes into my mowing session when the engine would suddenly start to wane and surge, especially but not exclusively when going through taller or wetter grass (i.e. heavier load on engine). If I just stopped mowing but left the mower blade running it would go RRRRR (normal speed)-rrrrr-RRRRR-rrrrr… maybe a dozen times before it would resume normal operation and I’d go on with my mowing until it happened again several minutes later. If I tried to keep mowing while it was having the issue it would stall out and I’d have to restart it. Once it started doing this it would do it more frequently thereafter until I was done with mowing for that day. It occurred to me to try loosening the gas cap when a bout of the waning and surging began but that didn't have any effect.
Then on a subsequent outing it got to the point where I would have to turn the mower blades off and sit and listen to the engine go RRRRR-rrrrr-RRRRR-rrrrr… maybe 20 times before it would smooth out and I could turn the mower blades back on and get back to mowing for several more minutes before it happened again. If I didn’t turn the mower blades off it would stall out.
More recently it got to the point where I would have to pull the choke a little ways out for a bit to smooth it out and keep it running, even if I turned the mower blades off right away. And it started happening so frequently that after about the first 20 minutes of mowing I’d spend nearly as much time sitting in place listening to the engine wane and surge as I did actually mowing.
Now, this morning, it started behaving this way more or less as soon as I started mowing (albeit some admittedly tall, wet grass), before the engine had even really warmed up. I think it’s now to point where the mower is essentially useless.
If I’m just traveling on the mower but don’t have the blade running (i.e. lightest possible load) it hasn’t shown the problem at all.
Yesterday I called the only repair shop anywhere near my modestly remote location. They said that they could arrange to come get it – I don’t know how quickly – and that after it arrived at their shop they’d “add it to the queue” – meaning it would be AT LEAST 2½ weeks after that point before they’d even look at it, and then of course they’d have to repair it and get it back to me at some point after that. I can’t imagine how long my grass would be by the time they got it back to me! And I have an awful lot of grass, literally several acres of it! And my wife’s family is coming soon to see our new home for the first time!
I’m game to tackle the problem myself, but I have very little mechanical knowledge (all self-taught and last used many years ago). All the repair shop told me was what I already figured. It has something to do with the fuel delivery system; they’d have to have it in hand to figure out exactly what. They talked about ethanol in fuel, and I do buy such gas, but the manual says that it’s OK and I add Mechanic-In-A-Bottle to every gallon, besides; they said ethanol can cause water problems, nonetheless. They said if there’s water in the carburetor then it will need to be taken apart (but if that’s the case then why would the problem come and go, and not affect the engine if the mowing blades aren’t being used?). They mentioned the fuel filter and at least one or two other things that went right by me. NONE of my mechanical experience has ever involved fuel delivery system issues; I’d probably recognize a carburetor if someone showed me one, but I’ve never done anything with one.
But if anyone can offer clear, detailed instructions on how I can diagnose and repair my machine, I’ll give it a go. At this point I really don’t know what else to do.
Sorry to make you read through all that, but I wanted to make sure I fully described the situation. Thanks for your time, in any event!
Gerry
