Bleeding fuel line on KX 121-3 Excavator Engine

[ThomasKeaton]

I cleaned the fuel separator bowl. I tried to bleed the line after putting it back on. It started and then died.

I then kept the ring on the bowl loose and loosened the nut on the injectors at the engine.

Fuel is coming out at the injectors. However, it will not start.

I do not know what to do now.

 

[85Hokie]

I cleaned the fuel separator bowl. I tried to bleed the line after putting it back on. It started and then died.

I then kept the ring on the bowl loose and loosened the nut on the injectors at the engine.

Fuel is coming out at the injectors. However, it will not start.

I do not know what to do now.

I am thinking if the ring on the bowl is loose - then you are going to suck in air -if you have not seen this - look here:

http://www.orangetractortalks.com/2008/11/how-to-bleed-kubota-fuelinjector-lines/

 

[rentthis]

I have several Kubota excavators and have that problem often. The pipe fittings where the fuel lines connect to the separator were the problem. They will sooner or later loosen up and leak enough air to cause the machine to not run or run poorly. If you can move one or both of the brass fittings with you fingers, mix up some JB weld and reseal the fittings at their bases. Just smear it all the way around with you finger. After it hardens, the machine should go back to work. If this works, replace the separator. It's only a temporary fix. Kubota sells an upgraded version that works. this might not be you problem but the JB Weld thing is worth a try. I have replace at least 6 of these separators.

 

[CountryBumkin]

I cleaned the fuel separator bowl. I tried to bleed the line after putting it back on. It started and then died.

I then kept the ring on the bowl loose and loosened the nut on the injectors at the engine.

Fuel is coming out at the injectors. However, it will not start.

I do not know what to do now.

Tighten the bowl once the bowl is full of fuel. Then move over to injector lines - loosen them. After you get fuel out of the injector lines, you need to tighten them back up again to start. I hope this is obvious to you.

 

[ThomasKeaton]

According to the videos on this site and the book, fuel is supposed to come out of the injectors when you crank the engine. I talked to the fellow at our local dealer and he said that plenty of fuel should be coming out. He said if it was not a good amount of fuel then there is still some blockage.

I will tighten the bowl back tight and see if I get a good amount of fuel coming out of the injectors.

If I get some fuels, I will tighten them up and see if it starts.

One thing the book said to do was to open the sir relief valve. It does not say where the air relief valve is. From the videos on this site, the valve is obvious for the tractors. It is not obvious on this engine.