Hi,
I have a 1956 olds holiday and I am working on a few issues.

My fuel gauge reads E. I believe I can test by grounding the fuel sending unit wire. Does anyone know if this wire exists the sending unit and goes into the trunk?
Is there a way to test by the gauge?

My driver side door is very hard to open. It usually takes a few tugs. Any ideas on what to check or what to lubricate?

Thanks for the help,
Brian

 

I don't know where the wire enters/exits the trunk to the sender on a 56, but you can test the system with the key on. With the sender wire not connected (open) to anything the gauge should read all the way full or past, if you touch/short that wire to ground the gauge will read empty. The sending unit on your car is 0-30 ohms where 0=E and 30=F.

 

First check the ground at the gas tank. It should be grounded with a clamp on the gas line which often is corroded and giving a **** poor ground. Most of us with this problem drill tap a screw and ground it on the frame.

If for some reason a splice anywhere on the gas line has been repaired with a rubber hose you will lose your ground. Always good to check that.... Tedd

 

Ted is correct, but in this case its not a ground because the gauge would read past full.

 

Yep, my mistake.... Tedd

 

Thanks everyone for the help.
I agree that the clamp is a likely culprit and seems to be weakened by design, corrosion and changes to the fuel line.
I will certainly check that next.

I am under the dash (addressing a headlight switch rheostat broken spring).

Based on the comments above, I would think that disconnecting one of the 2 leads (grey and yellow) going into the gauge would cause the needle to go to full correct?
I tried unplugging both, one at a time, and could not get any movement. I am suspecting no power.

Will check. Does anyone know which wire carries power and where it comes from?
THanks,
Brian

 

I checked and I have almost 12 vdc to the yellow wire.
When I ground the other lug, I get no movement of the dial. Does this suggest the gauge is bad?

 

This is the typical fuel gauge wiring. The gray should be from the tank, if you disconnect it with the key on the gauge should go to full.

 

Thanks for the diagram. The dial does not move with the gray lead disconnected and I get 12 vdc at the yellow lead, so I imagine the gauge is broken.
Does anyone know where I could get a new gauge?

 

One more thing to check is the ground to the gauge itself.

 

The dash ground check is a great idea. Was also thinking...what if the leads were reversed?
in my checking... I never pulled both out, at the same time (to prevent this, but never considered reversing the wires).

will try a ground strap to gauge

 

Try 2bl442 on this site he(john) is parting out a 54 and a 55 Old's may or may not have have some dash gauges on one of the cars I Know one of his cars is missing the dash when he got it. Other wise it's Ebay

 

Update:
I swapped in another fuel gauge and that seemed to address the fuel gauge never going to E problem.
I would say that, in all likelihood, this may have been a dash grounding issue as the old gauge moves freely with no visible issues.
If anyone is facing similar issues, I would say that a properly grounded fuel gauge, in the dash cluster, should result in the needle moving from the 0 to empty. If someone has an issue where the needle is stuck at zero, and removing grey wire or grounding the lug has no impact on the needle, they may want to reseat the gauge, which can be done with the cluster in place.

So, that solves the fuel gauge issue, but I believe I now have an issue at the sending unit.
If I disconnect the lead, at the trunk, I get full.

I traced the fuel line back to the tank, and saw no visible clamp (although it might be on the top of the tank, which I have yet to access). Given that (1) the tank is full, (2) the dash gauge is working and (3) the fuel gauge reads full when the lead is disconnected at the trunk, does this mean that the tank gauge is stuck / defective or the lead is being grounded from trunk to tank?

 

If you ground the wire the gauge should go to E with the key on. Chances are your fuel tank sender is no good.

 

Folks I've read fully the posts dating from 2020: This problem is kicking my *** and I have troubleshot similar frustrations with my 58 Edsel!
When I sold it recently, the gas gauge was as accurate as they get.

When I bought the Olds I complained that the reading on the fuel gauge was on "E' big time please put some fuel in the tank.
They said they did, I suspected they were untruthful.

Once in my garage I pumped five gallons in and viola it registered 1/2 full. Horray no further probs.
Wrongo after a Victory jaunt around the neighborhood it was consistently on "E" again...

Tearing up the trunk floor mats I used my Simpson 260 VOM, and resistance checked the sending unit. The service manual calls for a BURROUGHS BT-100 (no longer available)
All leads measure as if the tank is half full (which it is)

The lead from the dashboard reliably measure +12VDC when the ignition key is on (briefly as I don't want to burn the points)

I am an experienced Electronic Technician, and I am "on the ropes with this vexing condition!

Should I buy another fuel gauge and mock it up to connect to the sending unit?

Clutch Cargo:
And THANKS for locating the Oil Filter AND the master cylinder in my previous posts!!


..

 

I have a 1956 Holiday 88 which originally had an intermittent reading fuel gauge.
Checking the connections to the fuel tank float assembly found all of them corroded.
I've got clean good solid connections now, and yet the gauge won't move up past E.
I am at my wits end on this

Clutch Cargo

 

Mr. OldCutlass I found your posted detailed schematic of inestimable value.

I've lost Sugar Bear s response to this problem, but his guidance was step by step to narrow this vexing bugaboo down!

I set up a mockup test fixture to simulate the system. Out of the car and with 30 Ohms dialed in it deflects the meter to Full.
In the car, connecting the lead to from the tank sender wire to my test gauge I show 3/4 of a Tank!! YAHOO praise the Lord and pass the ammunition.
This absolutely rules out everything from the dashboard back...
The in-dash meter still is stuck on E but it passes voltage thru it, so it is not open. AND it reads 70 Ohms pole to pole.

Conclusion anyone?

 

56holiday, PM sent.

 

How is the ground to the gauge connected?

 

The ground to the gauge is connected in two ways, by the metal housing of the instrument panel,
and, most importantly the INTERNAL ground of the meter itself which is often corroded.
The existing apparently faulty meter can be carefully dissembled and the reverse side of the meter
panel can be lightly sanded. In my case I had to bow the panel slightly to maintain good contact.
Judicious use of your smallest ball-peen hammer works well for this task.
Take care during reassembly of the back panel for the meter as I found it is possible "Murphy's Law"!
to orient it backwards the small tabs must find their slots on the main panel.

 

Did you see my post where I note the schematic is inaccurate in that it shows the power being grounded directly to the case?