new fuel pump but guage not working

[pugger]

I broke down and had to have a new fuel pump (in tank) fitted. The fuel guage hasn't worked properly since. It registers completely full for ages then quickly drops to halfway, but never below. The mechanic swears the unit is ok, but I'm not convinced...I've noticed diesel pooling around the seal of the pump, so i reckon he did a bad job of fitting it?
Any help appreciated - cheers!

[Doggy]

Hi & welcome to the forum.

Sounds like someone didn't make too good a job of changing it. The gauge sender is part of the lift pump assembly and it should just about be possible to swap this without damage to the pump or anythng else. Unfortunately, access is not always good enough. Some prefer to drop the tank, which makes access easy.

All too often, we see damaged / broken retaining nuts or seals, which can cause fuel leaks under the seat, with a full tank. In some cases people have crudely enlarged the hole in the floor to get it out through the top.

I would try to get whoever did this to sort it out, or recompense you in some way.