Fuel gauge dies


Paula W
 

After starting the car today the fuel gauge started bouncing wildly, with the center of oscillation moving slowing towards "E" and finally dying before my eyes. The car continued to run.
When we put the resurfaced gas tank in about 3 years ago, and it received a new sending unit.
The gauge cluster is a restored unit.
What I checked:
I checked the tank with my backup gauge (a wooden dowel) and there is plenty of gas. A circuit tester shows a very faint glow (almost imperceptible)  at the gauge connection under the dash (key"on").

Any other things I should try before jacking up the car and (gasp) removing the tank?


Spock Arnold
 

As with anything electrical, check your grounds.  Most likely the sending unit ground corroded.

On Tuesday, March 9, 2021, 10:18:42 PM EST, Paula W <paula_whitney@...> wrote:


After starting the car today the fuel gauge started bouncing wildly, with the center of oscillation moving slowing towards "E" and finally dying before my eyes. The car continued to run.
When we put the resurfaced gas tank in about 3 years ago, and it received a new sending unit.
The gauge cluster is a restored unit.
What I checked:
I checked the tank with my backup gauge (a wooden dowel) and there is plenty of gas. A circuit tester shows a very faint glow (almost imperceptible)  at the gauge connection under the dash (key"on").

Any other things I should try before jacking up the car and (gasp) removing the tank?


crosleyshortsport
 

I am 99 and 9/10 sure you have a sending unit that is not grounding to the body of the car. It only takes a year or two of a bit of moisture in the air to cause a ground point to start to corrode. So, your sending unit is grounded to the tank by the screws that hold it to the tank. Then your tank is grounded to the body with the bolts that secure it to the body. ANY electrical issue on a Crosley,....check your grounds, check your grounds, check your grounds.  Hope this helps, Jeffrey


On Tue, Mar 9, 2021, 10:18 PM Paula W <paula_whitney@...> wrote:
After starting the car today the fuel gauge started bouncing wildly, with the center of oscillation moving slowing towards "E" and finally dying before my eyes. The car continued to run.
When we put the resurfaced gas tank in about 3 years ago, and it received a new sending unit.
The gauge cluster is a restored unit.
What I checked:
I checked the tank with my backup gauge (a wooden dowel) and there is plenty of gas. A circuit tester shows a very faint glow (almost imperceptible)  at the gauge connection under the dash (key"on").

Any other things I should try before jacking up the car and (gasp) removing the tank?


David Stubenvoll
 

6volt systems are very sensitive to grounding and also to wiring gauge. Voltage is pressure, amperage is the fuel, and wattage is the amount of work done. Since a 6 v is half the pressure of a 12v, it needs to push more amperage to get the same amount of work accomplished. That’s why older cars have much larger diameter or gauge of wire, bigger hose - less pressure = same result as high pressure smaller hose, i.e.  6V versus 12v. Grounds are essentially part of the wiring circuit and therefore must be better in a 6 volt system than in a 12. 


Don Pitchford
 

Not to hijack the thread, but I have a related question. Does anyone here know the proper resistance of the gas gauge sending unit? I see some aftermarket sending units listed as 60 ohms and some as 90 ohms for full scale reading on the gas gauge. Since none of the gas gauges work properly on any of my 3 Crosleys I plan on doing some troubleshooting on them this Summer.
Thanks, Don Pitchford

On Tuesday, March 9, 2021, 09:18:42 PM CST, Paula W <paula_whitney@...> wrote:


After starting the car today the fuel gauge started bouncing wildly, with the center of oscillation moving slowing towards "E" and finally dying before my eyes. The car continued to run.
When we put the resurfaced gas tank in about 3 years ago, and it received a new sending unit.
The gauge cluster is a restored unit.
What I checked:
I checked the tank with my backup gauge (a wooden dowel) and there is plenty of gas. A circuit tester shows a very faint glow (almost imperceptible)  at the gauge connection under the dash (key"on").

Any other things I should try before jacking up the car and (gasp) removing the tank?


Richard Williams
 

Your tank has lost the ground. I had the same problem. I ran a ground wire from one of the sending mount screws up to the back of the instrument panel mount screws. Problem solved. Good luck. Rich W.

On Tuesday, March 9, 2021, 07:18:42 PM PST, Paula W <paula_whitney@...> wrote:


After starting the car today the fuel gauge started bouncing wildly, with the center of oscillation moving slowing towards "E" and finally dying before my eyes. The car continued to run.
When we put the resurfaced gas tank in about 3 years ago, and it received a new sending unit.
The gauge cluster is a restored unit.
What I checked:
I checked the tank with my backup gauge (a wooden dowel) and there is plenty of gas. A circuit tester shows a very faint glow (almost imperceptible)  at the gauge connection under the dash (key"on").

Any other things I should try before jacking up the car and (gasp) removing the tank?


Paula W
 

Don - In case you want to try yet another fuel sending unit, we got our fuel tank sending unit from Service Motors. It worked right away until this (hopefully) grounding problem. I never inquired about the resistance of the wires, however. Dale at Service Motors may be able to tell you.


Don Pitchford
 

Paula,
Thanks for the information. I figure I will need to order at least 1 or 2 new sending units since one fell apart when I removed it and another has never worked since I got the car many years ago. When I get a new one I'll measure the resistance. My main reason for wanting to know the value is that I build a lot of "test fixtures" so I can isolate problems as quickly as possible. 
Thanks, Don Pitchford

On Wednesday, March 10, 2021, 11:52:43 AM CST, Paula W <paula_whitney@...> wrote:


Don - In case you want to try yet another fuel sending unit, we got our fuel tank sending unit from Service Motors. It worked right away until this (hopefully) grounding problem. I never inquired about the resistance of the wires, however. Dale at Service Motors may be able to tell you.


Paula W
 

While my sending unit ground problem persists, may I still use a Battery Tender on the car? (I'm only just learning about electrical systems on older cars and all the first chapters of my resources emphasize safety, as they should.)

Alternatively, I'll can take the battery out of the car, but would prefer not too.


David Stubenvoll
 

If you want to err to the super safe side, keep the tender on the battery but disconnect at least one if not both of the terminals from the car. 


Jim Liberty
 

Just disconnect the ground at the battery when you work on anything electrical.      ................Jim.

On Wed, Mar 10, 2021 at 1:54 PM Paula W <paula_whitney@...> wrote:
While my sending unit ground problem persists, may I still use a Battery Tender on the car? (I'm only just learning about electrical systems on older cars and all the first chapters of my resources emphasize safety, as they should.)

Alternatively, I'll can take the battery out of the car, but would prefer not too.


Richard Williams
 

I use a battery tender on my cars all the time. You will be just fine with it in the car connected.

On Wednesday, March 10, 2021, 01:54:45 PM PST, Paula W <paula_whitney@...> wrote:


While my sending unit ground problem persists, may I still use a Battery Tender on the car? (I'm only just learning about electrical systems on older cars and all the first chapters of my resources emphasize safety, as they should.)

Alternatively, I'll can take the battery out of the car, but would prefer not too.