leroycjr

So today i cleaned up, retaped, and installed my old rear light harness. And i have a few questions. Outside of the side markers bulb, tail light connects, back up light connects and license light........does the fuel sending unit connect in this harness and if not there where?

Reason I say this is in the attached pic it looks like someone tried gerry rigging the sending unit by splicing the unit wire into the license lite (tape lump). I found the actual clip which the dummy snipped off i might be able to use it but it is pretty short. Which comes to another question.

So Ive read a lot of posts about gauges setting at E or F and never moving. Well mine is and always sits close to E. And if i understand correctly that means zero resistance. Its also still spliced into the license wire (which has no bulb) AND if my thinking is right because of the dumb splice the gauge would onlywork when the lights were turned on to power the license light. So once i fix the the splice and connect to the right connection....if the unit still sits at E then i need to replace the unit correct??? Also i need to double check the ground.

After those checks are done is there anything to do with the gauge before i drop the tank????

leroycjr

(History teacher voice)
Anyone, Anyone............

Rickman48

I'd figure a way to positivly determine that's the sending unit wire, and the guage is working, first.

Allan R

Yes.
Have a look at Page 12-200 of the 72 CSM. It shows the fuel tank wire lead hooking up with the rear harness. You will also need to disconnect the ground strap on the fuel tank, and obviously drain the tank before dropping it.
http://wildaboutcarsonline.com/membe...al_Sect_12.pdf

Tony72Cutlass'S'

Agreed on what Allan describes in WAC.

On a side note, i also dropped by fuel tank last weekend. PLEASE support the underside of the fuel tank before you drop it. I had to cut out my bolts with a hacksaw. and when i cut through the last bolt... SLAM. the tank hit the jackstands i had underneath.

Trust me, you're not going to want to be the jackstand.

Allan R

Best description I've heard yet on this. Words I will live by later this spring...

jaunty75

This is correct. It means that somewhere in the line between the fuel gauge on the dash and where the other end of that wire is at the trunk area, it's shorted. Disconnect that wire from whatever it's attached to at the trunk end, and, with the key ON, the gauge, if it's working properly, should move immediately to F or probably way past it as F means 90 ohm resistance, and an open circuit would be infinite resistance. If that happens, your gauge and the wire from the trunk to it, are OK.

Find the wire coming from the sending unit and attach it to the wire coming from the gauge, and, if your sending unit is working properly and the other wire coming from the sending unit is properly grounded, the gauge should display the amount of fuel in the tank.

The ground wire from the sending unit is not visible in the trunk area. It usually just comes off the sending unit and attaches to the body or frame somewhere under the car. It's a common problem source if the connection has become corroded. A bad ground would lead to an open circuit situation again, and that would mean a reading at F or beyond.

leroycjr

Thanks to all
I'll be trying to get under there this weekend.

Mental note: DON'T BE THE JACKSTAND!!!!!!!!!!

Tony72Cutlass'S'

I supported the gas tank by two jackstands. one on the passenger side, one on the driver side. (the straps kinda hold it in at the back end).

After i had the bolts and straps loose. I got outta there and used a floor jack to raise the tank by a half inch, and then removed the jackstands. and dropped it slowly.

Keep in mind, if you work on the floor like me. You'll need to lower the tank. and jack up the differential a little bit to get it clear. Otherwise the tank won't leave the underneath of the car.

My tank is ugly and rusted, so i didnt care if i dinged it up a bit. If you plan on keeping yours, be careful when you remove it not to puncture something.

Allan R

Actually I won't need to jack up the diff. I'm planning to replace the rear bumper at the same time so everything should be wide open. A little different approach to solve the same problem.....

Tony72Cutlass'S'

I've dropped the rear bumper on myself too

They used to call me jack danger...

Allan R

We'll have to rename you to Austin Powers. Danger is his middle name.....yaahhhh baaaaabyy!

Tony72Cutlass'S'

Hah! too funny, i'd like to make a comprehensive list of movies that 4-4-2's have been part of.

Or i could be this guy!