dodgy fuel gauge

hi everyone me little vans fuel gauge is not telling me the full story. it seems that if I fill the tank up it will read a full tank but when it it gets to a quarter off a tank it stays there until it runs out and the fuel light does not come on. do you think check the wiring or replace the sender or thrash it with a stick.  can the wiring and sender be checked as it is or do I need to drop the tank. thanks

I would say you have a kinked float tube.

Which will most likely cause by the bottom of the tank bent inwards a little bit.

Take the tank off, remove float tube, check for slight kink.

If it is, take the pump out as well, put the tank onto some blocks of wood then bash the bottom out through the pump/float holes using a length of 3x2 timber and a big hammer.

Then warm up the float tube with a fan heater , hair dryer etc to soften the plastic and massage out the creased section.

I have looked at the tank and it looks like a small dent where the drain bolt is because the bolt is at a slight angle so I,ll have to set a day aside to investagate thank,s for the advice

The bottom falls off the tube, causing the float to stick. Def the problem if it takes a while to get to full after you have filled it.

it seems to go to full straight away. if the float does not reach the bottom off the sensor will that stop the fuel light working