Fuel gauge ohm rating

chas427fe · #1 (**permalink**) 03-22-2009, 08:29 PM

I want to replace the fuel gauge that is in my car. How can I find out what ohm rating it is. I can't find anything on the gauge and have tried putting an ohm meter to the pickup, When I put the ohm meter to the pickup it bounced all over the place. Any suggestions or ideas or do I just need to replcae both the gauge and the pickup? Thanks, Chas

Dangerous Doug · #2 (**permalink**) 03-22-2009, 10:45 PM

ERA has a good write up that includes some stuff on fuel guages. Check out www.erareplicas.com and search for "Wiring Primer".

Changes are, your fuel guage IS an ohm meter---of sorts. It's measuring the resistance of your fuel level mechanism.

DD

Ronbo · #3 (**permalink**) 03-22-2009, 11:19 PM

As I recall 60 ohms was standard (GM) for most aftermarket gauge mfgs. (60 ohms empty) Ford used some goofy, non-linear, 25 - 80 ohms sender.

strictlypersonl · #4 (**permalink**) 03-23-2009, 04:56 AM

It would help if we knew what gauges you're using. But even among a single gauge manufacturer, there can be multiple range choices. First thing: If you disconnect the wire from the sender, does the gauge go to zero or full?

chas427fe · #5 (**permalink**) 03-23-2009, 09:08 PM

Thanks everybody for your replies. The gauge is a Faria which makes marine gauges. I went to their web site and could not find anything. When you disconnect the wire to the sender it goes to zero. I disconnected the second wire to measure ohms again. I don't know who is a bigger idiot me or the original builder. I didn't realize he did not use two nuts on each connection and spent the last half hour fishing the sender out of the tank. After fishing it out and checking it outside of the tank I got readings of 280 ohms at empty and 55 at full. Looking at Summit they have three available: 1: 240 empty and 33 full, 2: 0 empty and 90 full and 3: 16 empty and 158 full. It looks like the 240 to 33 is the closest to what I am getting off my meter. Chas

strictlypersonl · #6 (**permalink**) 03-24-2009, 05:04 AM

I found the sender specs on the Faria site. 270-33 ohms.

Google is your friend.

Sender Specifications (PDF)

chas427fe · #7 (**permalink**) 03-24-2009, 05:56 AM

Stricklypersonl, thanks for the answer. I guess I need to get better at using google. Chas

strictlypersonl · #8 (**permalink**) 03-24-2009, 07:00 PM

One hint for searching:

You can search a single site (without going into the advanced options) by typing

<your search words> site:faria-instruments.com

in the search box.

chas427fe · #9 (**permalink**) 03-24-2009, 07:13 PM

Thanks for the suggestions.