Looks like this if you have a carb car, if fuel injection there is a fuel pump also attached to the end.http://www.ebay.co.uk/itm/MK1-2-SCIROCC ... SwyQtV3ai1
Could just be the float it stuck or rusty connection.
If the car has been sat for a while it's worth having a good look inside the fuel tank, get a torch and have a good look, if rusty bits in the fuel tank get a magnet on a stick etc and try to fish out as much rust as possible then clean the magnet and drop it in the fuel tank then it will collect any other bits of rust while in there, don't put the magnet to close to the fuel sender float as you dont want that to stick to the magnet!
To remove the fuel sender from the tank you only need to turn it about 30 degrees then it should lift out, watch out for the rubber o-ring and make sure there's a good seal when putting it all back together or you will get a fuel leak/smells from the tank.
If your sender is plastic you will need to make/get creative a tool to slot into the grooves to turn the sender, if it's metal you can use a metal bar and hammer to hammer it around, you only need to move it a little to free it up.
Mk1 78 Scirocco GLS 1.6 FR, weekend toy.
Mk1 88 Golf GTi cabriolet 1.8 DX. Daily drive.
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