Kubota z121s

[larryrf]

I purchased a z121s last year. Has been doing a great job. A few days ago I was mowing a large yard. After about 35-40 minutes into it, the
Mower started to die. I brought the Drive arms back to neutral pushed the PTO off. The motor picked back up and ran fine. Mowed a while longer and same thing happened again. Did this several times. I checked air filter and took off the foam rubber pre cleaner. It was pretty dirty, but the air filter seemed to be clean. It did it a few more times and would nearly completely die. I choked it and it ran pretty we'll again for a while, so I'm thinking the fuel filter is beginning to stop up. The last few times it did it , it died completely. When I went to crank, it would only click (starting solenoid). I still think it may be the filter, but what's up with it not turning over? After it sits and cools a bit, it cranks like new.

 

[GreenGuy23]

I have a ZD323. I had similar problem with mine. It ended up being contaminated fuel. It would be for a while but as I would go along it would collect in the pickup tube on the tank and stop it up. My ZD323 is Diesel but it was having similar problems.

I took the side panel off and was able to access the fuel pickup tube. I drove it around until it started to die and the shut it down. I removed the pickup tube and blew it out with the air compressor. Haven't had trouble since.

I would see about dirty fuel.

The not cranking I dealt with too. It ended up being a safety switch on the brake pedal.

 

[larryrf]

GreenGuy23, thanks for your reply! I think it's something to do with the fuel system also. I talked to the service supervisor at the dealership where I purchased my mower. He said that he thought it would be some kind of trash building up in the pickup tube. He said a Kubota rep told him that they have been having problems with owners complaining about the same thing. He said the rep said to cut the bottom of the pickup tube at about 45 degree angle no more than half an inch up. That it help keep the tube from sucking trash right off the bottom because there's so little clearance at the bottom of the tube. I've taken the tube out and trimmed it like he suggested and also changed out the fuel filter just in case. I did not find anything in the tube nor could I see anything settled in the bottom of the tank. Maybe it will help. As far as the ignition clicking and not turning the engine over, he said that there is a safety switch that helps keep from burning up the starter from constant cranking, or prolonged cranking. I don't know. Never heard of that, but not saying it's not true. Next time I mow I'll find out if it's helped it out. The way it did last time, it started when the motor warmed up a little. Will let you know. Still not ruling out electrical problem somewhere.

 

[GreenGuy23]

No problem. I hadn't heard about cutting the pickup tube. I may look into that. When I was having that problem I caught it about killed the mower. I got it back to my shop as quick as I could and popped the tube out. Once I hit it the with compressed air there was this big wad of grass and rust particles that shot out. The rust particles came from the diesel storage tank we used. Both tanks were doing that.

I hadn't heard about the safety for the cranking either. Mine ended up being the brake pedal sensor that is wonky.

 

[larryrf]

GreenGuy23, I kinda think my problem will end up being a safety switch going bad. The fuel system seemed to be too clean. The fuel pickup tube thing may keep the tube from clogging up at the bottom of the tank, but I think that some of the trash will go up the line to the fuel filter, but that's what it's for, plus it's easier to get to and change out than pulling the tube out of the rubber grommet that seals it off. Anyway, it's been raining here so it's going to be a few days before I can mow and check it out. Thank for your response. Have a great weekend!