Not to long ago I replaced the fuel sender in my 79 sb. I bought it from Advanced Auto and did not look like the original. The float is a plastic square box compared to the round float that it did have. Well anyway I filled up today and it onlt took 10 gal. and my gauge was just above "E". That doesn't sound right does it??? The tank is new and is mounted behind the axel.

 

I did the same thing w/ the same sending unit from Advanced about a month ago and mine does the same thing. I'll fill up and drive about 20 miles and it was only reading about half a tank, meaning i used about 9.5 gallons of fuel. Wrong, it only took 2 gallons to fill up. I wasn't sure if mine was attributed to the sending unit or crappy old gauge. I'm wishing I had replaced it with a sending unit w/ the original type of float. Glad you asked the question because I thought I was the only one.

jb

 

The sending unit is adjustable

 

How?? There was no paper in the box telling how to do it?

 

I'll have to look it up, it's been nearly 15 years since I have done it.

I know the "least" you can do is bend the arm and play with it that way, but that is quite the process if you still have the bed mounted.

Josh

 

Have,
__you tried checking your electrical connector or it's ground?
Yeah, I know it's a pain.

 

Actually I had the bed off the truck when installing this. I cleaned everything good.

 

Did,
__you inavertly open the contacts, or did close the contacts by sqeezing them?

 

I'm not for sure what you mean?

 

Uh,
__lemm'e see about gitting some pic's.

 

Here,
__I'm talking about those terminals inside the pigtail.
You can pull the teminal into itself, like rolling up sheet of paper into a tube. By sqeezing them gently.
I just take one of my excact size drill bits & clean the inside of the terminals by hand. (Not shave, clean the walls.)

 

Oh I see, no I didn't do that I just unplugged from the old and plugged into the new one.

 

Then,
__it may be not getting full contact to stud terminals & causing flux/inaccurate readings.
Plus, some sending units don't have the same size threaded terminal studs.
(There usally smaller.)

P.S. don't forget to check your grounds at your Gage Cluster.
Plus put a ground to the chassie from the battery.
This should help.

 

Here,
__buzzurd- is the thread you need.-

 

Buzzerd,
__just in case you are not at the other page. https://www.ford-trucks.com/forums/7...uel-gauge.html
Here.

There,
__was no manufactured chassie ground.
You have to put one in. Two ways of doing this.

1. run batt.cable (no smaller than 6-ga.) from ground on battery to a bare metal spot on chassie, use a spiked washer (makes a more correct contact.) inbetween cable & chassie. Don't forget to put DIELECTRIC sillcone grease on the parts & chassie. (This grease is the same stuff you put in your spark-plug boots.)

2. run ground from engine block to chassie. Don't forget your spiked washers & D-grease.

TIP: your original ground should be going from your battery to your Engine block,
Directly to your block.

NOT to a bracket, intake bolt/nut, exsast manifold nut/bolt, Or even to the engine head.
Only, Directly to your block.
This the one & best soild route to grounding the block.

I have no less than 3 grounds on my own trucks & cars. (one to engine, one to chassie, & one to the body.)