Someone was having problems with their Toro 580D . They said that one wing was not cutting. I had the same problem and spent several hours diagnosin

[Bigmowerguy]

Someone had a problem with their Toro 580 D . One wing was not cutting or turning fast enough. This was the exact problem I had. After several hours of research and a little $, I discovered it was a 1.50 set of rubber o rings that were old and broken on one of the valves in the hydraulic block. Unscrewed the valve going to that wing, replaced the o rings, retightened the valve body and wham, it worked again! Hope that helps!
Problem I'm having today is that I ran my mower let it idle down a bit and turned it off. Went back to start it again and yikes! No power to key switch or lights but battery tests good?! Wondered if it could be a fuse or something?

 

[mechanic mark]

Possibly yes, check all connections by hand making sure they are tight & secure, especially ground cables, ignition switch wires, etc. & free from moisture. I use Silicone Dielectric Grease on electrical connections.

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