I have a older Kubota kx71 with a V1505, It just recently started dumping diesel fuel into the crankcase or oil. It’ll fill up the crankcase to the point where there is diesel fuel and oil coming out the overflow on top. This issue started happening after I change the oil. This engine has an electric fuel pump not a mechanical one so I don’t know if that rules anything out. Does anyone have any ideas of what could be wrong. Any help would be appreciated. Also does anyone know where I could download a service manual for this machine.?
Kubota KX71 with v1505
- Thread starter bearmanly
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jwkirkpatrick
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KX41-2,L3901DT FEL,RCR1872,BB2560,RTV1120D,ZD326,MX5100F FEL,FDR3690,M108S,Z125E
That is similar to what happened on my KX41 when the fuel pump was worn out. Mine is mechanical though and I had to have it rebuilt. Another symptom was it wouldn't cut off with the key. I had to reach back and pull the lever on the fuel pump.
My excavator also does not turn off with the key, I have to pull the choke to get it to turn off.
North Idaho Wolfman
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L3450DT-GST, Woods FEL, B7100 HSD, FEL, 60" SB, 743 Bobcat with V2203, and more
First and foremost there is no choke on a diesel, so it sounds like you're pulling the manual fuel cut off cable or linkage.
If it doesn't have a mechanical lift pump then there is only 2 ways for fuel to get into the oil.
Bad injection pump seals, you'll need to either have the pump rebuilt or replace it.
And far less likely, is an injector that is bleeding down into the cylinder, this is usually accompanied by a very poor running machine.
If it doesn't have a mechanical lift pump then there is only 2 ways for fuel to get into the oil.
Bad injection pump seals, you'll need to either have the pump rebuilt or replace it.
And far less likely, is an injector that is bleeding down into the cylinder, this is usually accompanied by a very poor running machine.
Thank you for that information I did not realize that a diesel doesn’t have a choke. This is my first machine and I’m new to working on diesels. Once I change the oil and bring the level back down to normal, the engine runs great. So I’m guessing it’s not a problem with the injectors. Another bit of information I forgot to share, is that right before this problem started I welded a thumb to the boom arm. Could that do anything to the electric fuel pump or make it over pressurized.? I’m just hoping it’s anything other than the injector pump. LOL
I was looking underneath my machine and noticed that the electric fuel pump is not made by Kabota. It’s a kyosan pump! Is this bad???
whitetiger
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Kubota tech..BX2370, RCK60, B7100HST, RTV900 w plow, Ford 1100 FWA
Kubota does not build electric fuel pumps, they out source them like all other manufactures do.
Wolfman can correct me if I'm wrong on this. On the Kubotas with manual shutoff knobs, the fuel shutoff solenoid only actuates for about 10 seconds when you turn the keyswitch off. If the battery were dead, the solenoid burns out, an electrical gremlin creeps in, or a mechanical issue pops up, you still have a way to kill the engine. I was lucky on my L35 and the hairpin clip that holds the link from the solenoid to the shutoff lever on the injector pump came out. All it took was a cotter pin. Since you're in that area, it's easy to check.
Good luck on your bigger problem.
Good luck on your bigger problem.
whitetiger
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Kubota tech..BX2370, RCK60, B7100HST, RTV900 w plow, Ford 1100 FWA
Kubota now on all engines mounts the shutoff solenoid into a hole on the block to the rear of the injection pump. A spring-loaded pin contacts linkage holding the pump in SHUTOFF position. When the key switch is turned to On and current is applied to RETRACT the pin letting the pump return to the RUN position.
Some of their solenoids have two wires, one positive and one negative. Others have two wires where one is a Pull circuit and the other is a HOLD circuit.
Most all of the injection pumps used by Kubota have a manual SHUT OFF lever on them that can be used at any time to shut off the engine.
Thanks for the correction. I've used an M7040 a couple of times and I don't think it has a manual knob, so I assumed . . . incorrectly.
Does anyone have a suggestion on where to get a diesel injection pump rebuilt? I live in New York, In case there’s somewhere local.
North Idaho Wolfman
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Equipment
L3450DT-GST, Woods FEL, B7100 HSD, FEL, 60" SB, 743 Bobcat with V2203, and more