JD450 C 1976 Fuel Issue?

[NIKinNZ]

Hello all, first of all i have to say, this forum is amazing! i have had to much help, and info to help me on my JD Crawler journey so i thank you all. My next issue (im a bit of a novice at this) is my JD450C seems to be (but with a full fuel tank) running out of fuel so for example i will start it up, start driving, it will be a bit weak, then the engine starts to die (as if running out of fuel) but then gets going again (for a minute or so) then dies and fully stalls out. The wire to the fuel pump solenoid is a bit dodgy, when it stops i will try and star it, usually it wont, but i wiggle the wire to the solenoid, then turn the key on it will click and then start but then same again, runs for 1-2 mins then stops again (Repeat...) .

My question is:-

1. Apart from initially starting, does the fuel pump solenoid work constantly when the crawler is going? i.e could this just be a dodgy wire issue?
2. Could it be a fuel pump issue? if so does anyone know of any aftermarket fuel pumps that will work with this model?

Thanks in advance.

Nik in New Zealand

[Jim B]

Haven't we discussed this before? The fuel shut off solenoid inside the injection pump has to remain energized (fuel on) for the engine to run. So yes, you could have a wiring issue. However, I would expect that to cause a run or not run condition, not reduction of electrical power; its either on or off based on power supplied to it or not.

Your 450C has two fuel pumps. The transfer or lift pump which moves fuel from the tank, through the filter and to the injection pump. The injection pump produces the high-pressure fuel supply needed at the injection nozzles and delivers it at the proper time for ignition.

When was the fuel filter last changed?

The fuel tank may have a screen in it where the line to the transfer pump comes out of the tank, which could be restricted. How well does the hand primer lever move fuel through the filter bleeder?

The governor ring may be failing in the injection pump. If you loosen the two screws that hold the small timing window plate, located on the side of the injection pump, enough to let fuel leak out a bit, does it stay running? If you put a clean white rag below the window and remove it are there small pellets that look like mouse droppings in the area? If so the injection pump needs a rebuild.

Do you have TM1102, the John Deere Technical (service) Manual for your 450C?

[Stan Disbrow]

HI,

And then there is the fuel tank vent tube. The one bugs love to nest in. May be a partial plugging. This runs from the top of the tank where the filler cap is, down thru the bottom of the tank.

Stan

[NIKinNZ]

Thanks for the replies, i will check those suggestions out, the filter was changed recently so can rule that out, as for the vent that is a possibility as is the wire to the injector pump solenoid, and yes Jim we did discuss that before, but i wasnt sure if it needed constant power to it (while running), or if it was just upon starting, my rational behind that was it would start but with movement and vibration etc the wire would move and lose electrical contact hence stopping. That is why im thinking it is that wire.

[wednesdar]

With mine, I just needed to disconnect the fuel supply hose to the injector pump and run air backwards through it. There was a little blockage that cleared. Issue never came back after I did this once.