Fuel sender woes

Ok so after a lot of effort, and research on here, I've traced my fuel problem to the sender unit on my disco, and it letting air in to the fuel stream. I'm not being tight, but I really can't afford an new sender right now. Does anyone know the usual place they leak from? If I can temporarily fix it up, I can survive till pay day. I can't see anywhere obvious as a place for it to be broken, annoyingly it looks in really good nick! Any info appreciated, cheers!