@jamesinc Sorry - couldn't reply to this until today as have been without signal in the bush.
@ramrod - good suggestion. Bridged the connection with a hair clip from Coles, but no change.
Cursed myself for not bringing a tool set. Cursed myself for letting NRMA expire. Cursed fate for making the schedule so tight.
Furiously called round every workshop, mobile mechanic, and recovery company nearby, but all flat out with existing work. Kevin (and he really deserves a shout out for being so helpful) at https://kwikstartmobilemechanics.com/ took pity and lent me some sockets and a driver from his workshop, so I got the plugs out, confirmed they were clean... and there was SFA petrol getting to the cylinders.
Hit both pump under passenger seat floor and bottom of fuel tank with tent peg mallet a couple of times and... she fired up! Provisional diagnosis is tired pump(s) + a bit of sludge from being run full to near empty twice in two days.
Quick test run and pulling cleanly under full load, so decided to roll the dice and keep going.
North of Brisbane, stopped at Bunnings to get some camping supplies. Came out to a perfectly flat front tire. Cursed the gods. Emptied the contents of the boot in a wet car park. Discovered that the wheel brace in the boot is from something german, and smaller. Cursed the gods some more. Then remembered I was at Bunnings and got a wheel brace for 15 bucks. Thanked the gods profusely.
Wheel changed, did an engine running stop at Supercheap for 3 cans of tyreweld, and made it to our destination near Amamoor only a few hours later than planned.
She started off the key for the return leg, but needed a bang on the pump after a brief stop south of Brisbane. Curiously, still not showing any signs of fuel starvation, even going up hills at 110km/h. Prudence means I'll be replacing both fuel pumps and giving the tank a flush.
Also decided to treat her to a new set of rubber as I'm now running different brands on the same axle, and the tyres are all pretty tired. Any suggestions for decent mid-range 940 rubber?
And lastly, the lesson I've learned from that little experience is always carry a set of basic tools and, even if it takes up a bit of space, a Volvo 'get out of jail' kit (inc. set of belts, fuel pump, fuses etc) is worth carrying.
After all, the costs of breakdown far from home (we were quoted $750 for a small hire car + $800 + GST to recover the Volvo) buys a lot of spare parts....