Hello! I have a Kubota B7800 Tractor (bought in 2008) that won't start. Before it stopped running, it would try to stall if foot was taken off the gas. As it died, it coughed and gave off white smoke. We cleaned fuel filter, and the bottle that goes over it. We tried bleeding the fuel line, but it didn't seem to do anything. It won't start but the engine is turning over when we try to start it. If anyone has suggestions please let me know! We're reluctant to call a mechanic for fear of the cost. Also if anyone happens to have photos of the parts mentioned in suggestions, please add them!! Thank you!!
Kubota B7800 (2008) Not Starting
- Thread starter dendriticdruid
- Start date
Well, a diesel needs three things to run:
White smoke can mean there's a lack of compression. (It cal also mean other very bad things.) But stalling when your foot is lifted kind of suggests to me it's not getting enough fuel.
I suggest you check the fuel flow out of the lift pump. Might be failing and not getting enough fuel to the injection pump. Just disconnect a line between the lift pump and the injection pump and see what you get when the fuel pump is operated. I don't know what kind of lift pump you have, so can't help there.
If that checks out okay, you might do a compression test as a next step. If you don't have enough compression, it's not going anywhere.
- Fuel
- Air
- Compression
White smoke can mean there's a lack of compression. (It cal also mean other very bad things.) But stalling when your foot is lifted kind of suggests to me it's not getting enough fuel.
I suggest you check the fuel flow out of the lift pump. Might be failing and not getting enough fuel to the injection pump. Just disconnect a line between the lift pump and the injection pump and see what you get when the fuel pump is operated. I don't know what kind of lift pump you have, so can't help there.
If that checks out okay, you might do a compression test as a next step. If you don't have enough compression, it's not going anywhere.
I had something similar happen with my B7500 a few years ago. It ended up being a very small split in the fuel line between the fuel filter and injector pump which caused the injectors to draw air.
Be sure the fuel is flowing freely out of your tank. Disconnect the first practical fitting after the tank and be sure fuel flows freely at that point. If it slows then stops you may have found your problem. Be sure you've got a good fuel filter and fuel flows freely through it. Of course you'll have to bleed the lines after this process. Clean any dust out of your air filter and make sure you have clear passage from there to the air intake. These are the basics and you can begin troubleshooting from here.