Kubota keeps stalling out

[dirttoys]

NORMALLY this is simple reduced fuel flow, could be in the lines, the filter, various pumps or the fuel pick up in the tank. Goofing with the injectors was probably a little cart before the horse, but, no sense in harping on it, but, it is probably the source of the banging you have now.
Pull the injectors one by one and have someone crank the tractor, you should get a solid squirt of fuel and then no fuel, then a solid squirt repeat ect...... .

I would guess if you haven't solved the original fuel issue, you will get light squirts (it will be hard to tell for you never having seen normal). After dorking with the injectors, you may have one with a steady flow, or one not providing fuel at all.

1. Thoroughly clean and test the fuel system.
2. Check the injectors as described above.
3. report back findings.
4 Please do not work on the IP.

Be careful testing the injectors, as the pressure can be high enough to break the skin.

Best,

ed

 

[WarrenPFJr]

So I loosened the fuel line to fuel injector number one which happened to be the one right behind the fuel tank. Immediately the knocking went away. I loosened the fuel line to fuel injector number two and tightened the fuel line to injector number one. The knocking came back. So I know I have an issue with fuel injector number one. I took fuel injector number one out and noticed some fine debris in the diesel film left on the end of the fuel injector. I cleaned the injector socket as best I could. I’m thinking maybe some dirt or dust got knocked in there from the hood of the tractor When I was reassembling. I took injector number two out and put injector number two into fuel injector one location and then put fuel injector number one into fuel injector number two location. I started the machine back up. I still got knocking it was not as bad. I loosened the fuel line to what is now fuel injector number one and the knocking stayed. I tightened that fuel line and moved to the new injector number two location. I loosened that fuel line, and then knocking immediately went away. so now I think I have a problem with that fuel injector. I’m thinking of replacing that single fuel injector. Is it OK to replace only one fuel injector?

 

[dirttoys]

So I loosened the fuel line to fuel injector number one which happened to be the one right behind the fuel tank. Immediately the knocking went away. I loosened the fuel line to fuel injector number two and tightened the fuel line to injector number one. The knocking came back. So I know I have an issue with fuel injector number one. I took fuel injector number one out and noticed some fine debris in the diesel film left on the end of the fuel injector. I cleaned the injector socket as best I could. I’m thinking maybe some dirt or dust got knocked in there from the hood of the tractor When I was reassembling. I took injector number two out and put injector number two into fuel injector one location and then put fuel injector number one into fuel injector number two location. I started the machine back up. I still got knocking it was not as bad. I loosened the fuel line to what is now fuel injector number one and the knocking stayed. I tightened that fuel line and moved to the new injector number two location. I loosened that fuel line, and then knocking immediately went away. so now I think I have a problem with that fuel injector. I’m thinking of replacing that single fuel injector. Is it OK to replace only one fuel injector?

Yup, don't fiddle with the others any more than necessary.

Best,

ed

 

[dodge man]

There are all sorts of things that could be going on now. There are copper washers that usually act as a seal under the injector. I’m not sure but I think they are a one use thing. Did you ever put a new fuel filter in it? Unless the filter fails it should catch dirt before it gets to the injectors.

 

[WarrenPFJr]

I did change the fuel filter after I got everything put back together and before I started it. It idles fine with the exception of the knock. This was an expensive lesson not to touch the damn injectors. Should have been a 15$ fix. The only reason I messed with them in the first place is the manual suggested having them tested at 1500 hours. I’m at 1200 and thought I ruled out the fuel filter by cleaning it.
I just picked up a new injector from the dealer for 380$ then found the same one online for less than 60$ I feel like I got ripped off. But education I guess can be expensive.

 

[YanmarFever]

Now you're getting somewhere, I would shop around on ebay for a rebuilt injector

 

[droy]

Almost certainly crud in the fuel system somewhere. You have to go through it from tank to pump. Second choice is the Fuel Shutoff solenoid. Best test there is to just plumb around it.

Cabbed L4740 having a power loss problem that is driving me crazy. Feel it is fuel system related, & so far I have drained & vacuumed tank, replaced fuel pump, air bleeder screw, MANY fuel filters, fuel filter assembly, all hoses. Cracking injector lines produces same miss each cylinder.
Now that you mentioned fuel shutoff solenoid was wondering if you could walk me through bypass procedure?
Power loss fairly constant but seems to worsen as operating temps rise. When shredding pasture tractor would come to a SLOW crawl when lifting 6’ rotary cutter & making turns. Wife has quit using tractor & now cuts our small pasture with ZD1211 zero turn. What she cuts at normal speed was bogging me down the tractor. Pasture is mostly kept cut like our lawn, so not talking about tall grass at all & power loss evident when using box blade & other tools. I did get algae in the tank, treated it, drained & vacuumed, still putting small doses of treatment jic but no evidence in filters.
Brought to local Kubota dealer; They kept it 3 & 1/2 months charged $800, drained tank, r&r fuel filter, proclaimed it cured. NOPE!

Sorry for hijack & long post but would sure like to get my tractor back to normal. Any advice / suggestions welcomed
TIA

 

[dodge man]

Probably a real pain to do but I’d take the tank off and clean it out again. My bet is where the fuel exits the tank is gunned up. Even though it’s supposedly been cleaned that’s going to be hard to do without actually pulling the tank.

 

[YanmarFever]

Warren, any updates?

 

[WarrenPFJr]

I decided to wait on the fuel injector coming from an online source. There are many vendors selling them for between 40-60$. I just can’t justify installing the one I got from the dealer which was close to 380$ after taxes. Dealer told me I could return it if it isn’t installed. So I’m hold waiting for the mailman at the moment. Purs like a kitten when idling on the 3 cylinders that are getting fuel.