Was loading some stuff yesterday and engine started to lug like it was running out of fuel. I checked gauge and it showed 1/4 tank roughly. Went ahead and killed it and poured in 5 gallons of fuel. Cranked it up and it was still rough. So I figured fuel pump was going out, which I had a spare. Went and got it and nothing. Ran jumpers from battery and both pumps would kick on. Checked voltage to the harness side of plug and had 12v. When I plug pump into harness I get nothing. Did some research last night and read where you can have 12v with a broken down wire and still not have enough current to run the pump. So I went out this morning and ran a jumper from the positive side of pump plug to battery and the ground plugged in to the harness. Pump kicked on. I tried it the opposite way with the ground just to double check and it wouldn't do anything by using the positive side of the harness plug. So I have concluded that the positive wire is broken down somewhere in the harness. What my question is, is where is the relay for the fuel pump? I would like to run a whole new wire if I can just find out where the other end of that wire goes. I surely do appreciate any help.
KX161-3 Fuel pump issue
- Thread starter Dyaser
- Start date
North Idaho Wolfman
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L3450DT-GST, Woods FEL, B7100 HSD, FEL, 60" SB, 743 Bobcat with V2203, and more
Your playing with fire just randomly adding voltage as there is a controller (computer) in there that controls the fuel pump.
I would suggest you get the WSM and follow the trouble shooting for the electrical to the fuel pump, it will very likely have a relay controlling it.
https://www.ebay.com/itm/Kubota-KX1...avator-Service-Repair-IN-BINDER-/223829948564
I would suggest you get the WSM and follow the trouble shooting for the electrical to the fuel pump, it will very likely have a relay controlling it.
https://www.ebay.com/itm/Kubota-KX1...avator-Service-Repair-IN-BINDER-/223829948564
This is a real long shot, but I'm throwing this out there as sometimes you need to look real close at the details...
On the glow plug relay, I found that Kubota used spade terminals that did not match the terminal size of the relay resulting in very poor contact or interference fit between the terminals. Two of the four terminals were correct and these are what provided the force and false impression everything was ok with the relay and socket interface.
Pull the relay out and insert a male terminal of the same size as the relay terminals and check each one to make certain there is ample interference fit (good grip)
Of course using a volt meter and voltage drop test could find this issue, but it sounds like you might not feel confident using one. (Not trying to be negative, just offering a reason why I mentioned the more mechanical test above).
In my case the female terminals on the power side of the relay socket were 3/8" and the relay used 1/4" terminals. Just so happens there is a very slight thickness difference between the two or it might have worked.
In any case this is not likely your problem, but it is cheap and easy to check.
