Jackaroos, corrugations and fuel pumps

If you own a Holden Jackaroo (1992-on) and are planning to drive on rough/corrugated roads, I recommend a small modification to the fuel pick-up (inside the fuel tank) before you depart. It will be much more convenient to do it at home before you leave than on the side of a dusty road somewhere in the middle of nowhere!

My Jackaroo (1995) stalled about 160km out of Innaminka on the Cordillo Downs Rd on the way to Birdsville. The engine would turn but wouldn't restart. After some quick trouble shooting, I established that the problem was most likely fuel related and decided to check/change the fuel filter. Expecting to have some fuel leak out as I removed the filter, I donned my safety glasses, and then was surprised that not a single drop of fuel come out of the line. This meant there was no fuel leaving the tank even though I could hear the fuel pump operating when I switched on the key switch. This meant the problem was inside the tank itself and would require removing the tank from the car.

When the fuel pump assembly was removed from the tank, it was confirmed that the pump was still pumping but the feeder pipe that runs from the pump out through the top of the tank had fatigued and snapped off just inside the tank. This occurred because the pump is rubber mounted (to protect it from shock, etc...) but it is basically hanging off the bottom of a bent metal pipe which eventually fatigues and breaks because of the weight and movement of the rubber-mounted fuel pump. This meant that all the fuel that was pumped, was never leaving the tank but just falling back down inside the tank. The pipe was then welded/brazed at the break and the pump put back in the tank, then the fuel tank was reinstalled.

In speaking to other travellers later in the trip, the problem I experienced is not uncommon for Jackaroos travelling the Outback (and doesn't even seem to be limited to petrol vs. diesel variants). In fact, when I first saw the pump assembly, I was not at all surprised that the pipe had fatigued and snapped off - to me it looked like an obvious design fault. It gave no further problems for the rest of the trip, but I was never completely convinced that the brazing hadn't just moved the same potential problem further down the fuel feeder pipe.

Before heading off on my next trip, I removed the fuel tank again (was getting quite good at it by now!) and removed the fuel pump assembly. I then cut the fuel feeder pipe about 2-3cm below the top and removed a section a few centimetres long. This section was replaced with some rubber fuel hose which provided some flexibility in the feeder pipe. A small bracket was then made to attach the 'bent pipe' section to the side support and prevent the pump from falling out of its lower rubber mount. The pump assembly was reinstalled in the tank which was reinstalled in the car which then successfully travelled the next outback adventure without fault.

Unfortunately I didn't think to take photos of the pump assembly while it was out of the vehicle so I can't provide any here - hopefully the diagram will be useful enough. No, I'm not going to take it out again just so I can post some photos!

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