Is it actually full? If you’re around 3/4 or a bit more you’ll be fine to change the pump without losing fuel. Otherwise, if your pump is dead, you’ll have to try to siphon from the filler, but I believe there’s an anti-siphon grate blocking it. The rear of the tank sits higher than the pump flanges, just under a quarter of fuel is stored there.

 

It’s very close to full. Sounds like I will have to remove the cover plates and filter flange and siphon from there.

 

The moment you loosen the pump flange lock nut, fuel will start coming out; which is very dangerous! Once the tank is filled over 3/4, the pump flange is anywhere from 1-6 inches below the fuel level. If you somehow removed the lock ring with no leakage, the moment you lift up the pump assembly, around 20L of fuel will start gushing out.

 

I think siphoning it after the cover(s) are off is your best bet, just beware of leakage like chewblekka said. Hopefully you have a powered siphon as it'll take a while to hand pump siphon out enough gas to do the job. Not to mention you're going to need a few good clean containers to hold all that gas before you put it back.

 

I suppose you could remove the return fuel line off the pump flange and attach a hose there.

 

I found this in a VW workshop manual.

 

I tried the return line on the flange but could not get any gas out of there and came to the conclusion that the gas level could be below the return line entry point. Upon removing the flanges that was indeed the case and used a 12-volt gas pump to empty both sides. The car now has two new pumps and flanges and running like new!!

 

Well done!