Fuel Gauge - Anyone have one whose not using it?

[33fromSD]

Hey All

When I got my 33 kit, I ordered the optional 6 gauge cluster which I used on my 33 build but I also got the stock individual 6 Auto-Meter gauges FFR includes with every 33 HR Kit.. That actually worked out great since I was doing a 55 F100 frame off restoration so I decided to use those individual gauges for that build.

Fast forward to today and the 33 is done (stored for the winter now, but had a blast in summer driving it) and I'm working on the 55 F100. I did the first run of the crate motor a couple weeks back and noticed the fuel gauge was reading full even though I only put 2 gallons on gas in the new tank. Ignored it at the time thinking it was a fuel sender or grounding issue I would look at down the road.

I finally got around to looking at it yesterday, and I believe the issue is actually the gauge itself. Found some odd stuff in measuring which is why I believe the gauge is bad.

Measurements:
* All wires connected --> short to ground on fuel sender (signal post on sender to frame, sender casing, etc).
* Signal wire & ground wire disconnected from fuel sender --> no short to ground measuring from fuel sender signal post to fuel sender casing or frame
* Signal wire disconnected from fuel sender --> no short to ground
* Signal wire connected to fuel sender, but signal disconnected from "S" post on gauge --> no short to ground
* Ground wire disconnected from fuel sender casing --> short to ground
* Ground wire connected to fuel sender casing, but disconnected from "GND" tab on gauge --> short to ground
* Signal wire on "S" tab and ground wire "on GND" tab on gauge disconnected (only 12V power connected to gauge), but signal wire & ground wire connected to fuel sender --> no short to ground measuring across signal wire & ground disconnected from gauge
* All wires removed from gauge (signal, ground & power) measuring across "S" tab & "GND" tab on gauge --> short to ground

I don't have another auto-meter fuel gauge to verify (maybe someone who has one can do a quick measure for me) but I'm fairly certain I should not have a short across "S" and "GND" tabs on the gauge itself.

My question is this, did anyone do what I did where they bought the optional 6 gauge cluster so they just have the stock individual 6 gauges just sitting around collecting dust on a shelf where they are willing to sell me the fuel gauge or if you don't want to part with just the fuel gauge, willing to sell me the whole set of gauges?

I'm not sure if FFR has changed gauges over the years but mine was a Gen2 kit and my gauges have a chrome bezel with a silver backing & black needle (see pic for reference). I'm asking the FFR forum since I called wauto-meter and they don't that particular gauge for retail so I can't buy it on line, it's a build for FFR only.

I "could" send in the gauge to Auto-Meter for a FA/repair for a "small fee" as they put it, but I only want to do that as a last resort.

Thanks in advance

Jim

20220124_101158.jpg

[Jeff33Ford]

You can buy a potentiometer and check the gauge.
https://youtu.be/vI5Gx3xf1R8

https://www.amazon.com/Valuepro-Pote...s%2C193&sr=8-3

[33fromSD]

Disregard, this is my stupidity. Which is really sad with an electronic background.

With the gauge completely out of the temporary dash I made there is no short (probably pick up noise or floating ground somehow).

I called AutoMeter again and he had me check the number on the inside of the gauge (pulled the incandescent bull) so he could verify the fuel sender needed for that gauge and the mistake was I interpreted it incorrectly originally. I thought I needed a 33(F)/240(E) ohm fuel sender and it's opposite, I actually need a 16(E)/158(F) fuel sender.

By having the wrong sender, even though the tank is physically empty (for the most part ~2 gallons), due to the wrong sender, the gauge is measuring full and since I was just using the continuity setting on my fluke meter verses measuring true resistance I was reading a direct short which I actually wasn't, I was reading ~40 ohms)

I ordered the correct fuel sender now which should solve my problem.

Jim

[FF33rod]

I was going to ask if the gauge range was properly matched to the fuel sender in the tank

For future reference, the standard FFR set of gauges from Autometer is the "American Platinum" model line. I don't think this is a standard line for Autometer anymore but you can find some gauges on their web site with a search and some of the aftermarket guys have some (Jegs, etc)

CHeers
Steve