bloody hell it happened again!!!!!
was heading up to madmacca's (also known as macca from the WTV's 'The 4WD Show) place when it conked out before the main hill, couldnt believe it happened again.
called up macca and he came round to help out. switched a few hoses, tried priming it, checked the tanks, checked the lines... ended up deciding it might of had a dodgy gauge and was low on fuel.
filled up the rear tank with 50L, so had 40L in it when it stuffed up, strange! primed it some more, messed around with the hoses, and eventually got it going and the air out of the lines. drove up towards macca's house only to have it stuff up again a bit further, and ended up priming it again, managing to drive it into his drive way whilst unhappily chugging and coughing away.
macca got to work and pulled off the main line solenoid, and we found that it indeed was the solenoid. when selected on the rear tank it was still slightly sucking out of the main tank, yet when on main tank it was fine.
bodged it up with a bit of spare hose and a few bolts and cable ties, and its running good as new! haha
again, macca, thank you so very much for all your help and for diagnosing my problem, you're a brilliant guy, a brilliant mechanic, and i cant thank you enough.
enjoy the tyres, and i'll see you out there on one of the trips haha!