Fuel Gage Sender Replacement Questions

[Greeness]

Working on a 1981 Avanti that has been heavily modified by the previous owner.  We have removed the rear seat and can remove the five screws (with difficulty) that secure the fuel gage sender but cannot remove the sender itself due to the fuel lines that are in the way.  Does the rear seat back shelf need to be removed in order to remove the sender unit?  If so, how do you remove the rear seat back shelf?  Among other changes it appears that the previous owner used pop-rivets to secure the rear seat back shelf to the chassis.

Additionally in order to remove the rear seat back we had to remove the tires in order to access the two nuts that secured the rear seat back.  Is this normal? 

Stephen

 

 

[Gunslinger]

It's not necessary to remove the rear shelf and it shouldn't be necessary to remove the rear tires.  You should be able to disconnect the sender wires and have access to remove the sender itself.  I'm not as familiar with an '81 as with earlier models so there may be differences I'm unaware of.  Does the '81 have an electric fuel pump inside the tank?  

[Avanti83]

It's possible that the fuel lines you describe are part of the vent system on top of the fuel tank. They are attached to the top of the tank in a couple of spots. You should be able to get at the hex fittings and unscrew them to get enough of the tubing out of the way. There are also a couple of studs on the tank that hold those lines up that have hex nuts holding the mounting brackets. IIRC

The fuel line is on the bottom center of the tank and feeds directly to the fuel pump along the frame and passes through a TEE fitting that will let you drain the tank if necessary.

 

Edited November 1, 2021 by Avanti83

[Greeness]

Thank you Gunslinger and Avanti83 for your replies.

My experience working on cars is almost nil so please bear with me as I ask these questions.

Even if we remove the vent lines above the fuel tank, there does not appear to be sufficient clearance between the top of the fuel tank and the rear seat back shelf to remove the fuel sender without bending the sender arm.  What am I not seeing?  Am I making the replacement of the sender unit more complicated than it is?

In regards to the rear seat back, it was secured to the chassis by two bolts and nuts.  We had to remove the wheels in order to reach the nuts.  Is the rear seat back fasted to the chassis using standard nuts and bolts or does it use a fastener that does not require access under the chassis and behind the wheels?

The only wires that I see entering the tank is for the fuel sending unit, therefore I do not believe that there is an electric fuel pump.

Finally, how do I edit the vehicle serial number in my AOAI profile?

Stephen

[Gunslinger]

My experience is with a Studebaker and a '70 Avanti II so your '81 might have significant differences as there were ongoing changes through the '80s...plus you said a previous owner made many modifications that could certainly impact what you're trying to do. 

I never had any problem changing the sending unit on either Avanti I owned that needed replacement.  The sender goes in pretty easily from my experience.  Remove the mounting screws (disconnect the battery first) and pull the sender out and reverse.  You may find it easier to angle the assembly out.

The rear seat back has two "hangers" for lack of a better word that the top of the seat back attaches to plus two bolts at the bottom that thread into a hole in the fiberglass at the bottom.  It's also not unusual for the threaded hole to be broken and you have to use a large nut and bolt to attach it through the body.  That would require someone with a wrench or socket holding the nut while someone up top tightens the bolt.  I've never had to remove the tires to accomplish that.

As I said...my experience is with earlier cars...an '81 may be different plus having to deal with mods someone else made.