I have a 1984 berlinetta 305 v8 4bbl carb. My fuel guage does not work so I plan to install an after market 0 to 90 ohm guage. If a hook the guage up to the positive from the sender unit and run a new ground will that do it? If the sender unit is good.
if the sender unit is no good is there a way to cut an access panel to access the top of the tank without dropping it?

 

Don't ruin your car by cutting a big hole in it. Drop the tank and replace the sending unit if you've proven the sending unit to be defective.

 

On my 92 rs you could drop the tank. This 84 berlinetta you need to remove the rear end and exhaust to drop the tank. There must be a better way.

 

Your 92 RS was EXACTLY the same as your current 84.

 

Welcome to TGO!

...you'll come to find that the subject of cutting an access panel to get to the tank has been a fiercely discussed topic going back many years. Very sore subject. That being said, only real issue I have with it (assuming you don't have a rare care, or gorgeous, stock survivor) is that even with the hole cut, it's still very tight, and properly and safely removing and an installing fuel lines can be an issue. My feelings on the issue aside, I dropped my tank and it wasn't as bad as I had expected. All things considered, I do think dropping the tank is the way to go.

With regard to YOUR issue....I'd look into getting your hands on a stock guage from one of our sponsors, members/classifieds, or a local pick'n'pull yard in your area and see if it's the guage or the sender. My sender would get stuck on full, and it would take a few days to come loose and accurately read. ...when I swapped pumps, whatever it was fixed itself (for now) and all is well. For now. LOL.

 

There is a right way and a wrong way. The previous owner of my convertible did it the wrong way, all he did was cut three sides of a rectangle (with a cutoff wheel!!!) and peel it back.




I was able to weld in some 16 gauge (the floor there at best is 18 gauge) and make an access hole in an oval shape. I figured, the car has already been cut so why not make a decent access panel?



I used riv-nuts and weatherstripping between the seal, seam sealer on the welds and a coat of paint.






BigMods along with some other members have the same concept on their cars too. https://www.thirdgen.org/forums/body...-previous.html

Many manufacturers have used access panels so they aren't inherently bad, it's the hack job that many people do that makes it bad. So if you are going to do it then do it the way I posted or that is posted in the thread I linked and do it knowing some purists (maybe even future potential buyers) will abhor your car for it.

 

And there ya have it , Tibo did a proper modification , whereas the guy before him did a hack repair . Tibo was handed an already cut car and made the best of it , a very fine access hatch indeed and has used the same type of compression fittings I'd use in a similar situation . Now for the OP's case , you have no option of doing the fine repair Tibo did because your tank is still in place , you'd have to remove the tank to do the nice panel Tibo did and since at that point your tank is already out , just replace the sender/pump with quality parts and put it back together .

So are you committed enough to the hatch idea to remove the tank to do it right , or will you just hack a hole and leave the mess like Tibo found ? The bottom line here is , to do either just the pump/sender replacement , or to do the pump/sender/install access panel the right way like Tibo's is , the tank gotta come out lest it's just yet another hacked thirdgen , the very reason why the access panel is usually SO frowned upon here .

 

Great job Tibo !

 

Last night I got around to testing the fuel system for leaks and being able to keep pressure. There was fuel dripping down the side of the tank so I removed the access plate and found out that the union in the main feed line was slightly loose. Tightened it up and everything is ready to go. Snapped a picture of everything installed.