Fuel gauge reading backwards on a 62

[1lobird]

I replaced the sending unit and bought a new equus gauge and mounted it next to the hood release handle. (looks pretty cool to me haha) still, it reads empty to full. I checked the wiring diagram and checked power going to the sending unit, all working. any suggestions as to how to fix it? appreciate it!

[jopizz]

How do you have it wired. Are you using the constant voltage regulator that's in the dash or do you have it wired directly to 12V. I believe you need straight 12V for it to work. Is your gauge specifically made for a Ford. GM gauges work completely opposite.

John

[simplyconnected]

"These Equus Analog Gauge Line gauges are perfect for any type of vehicle." NO THEY ARE NOT!
It upsets me when vendors sell stuff that does not work, then comes the disclaimers.

Evidently you bought a gauge that is 0-90 ohms meaning, the gauge reads Empty at zero ohms. That is not how Ford gauges work. When we disconnect our sending unit wire (greater than 90-ohms resistance) our gauges fall to 'empty' or 'Cold'. Our gauges ARE NOT GROUNDED. They are isolated from ground.

Here's what Equus says:
"Q: My fuel level gauge is not reading correctly, why?

A: There are two things that you need to make sure of when hooking up a fuel level gauge. First, do the ohm specifications of the sender match those of the gauge. Second, do both the sender and the gauge share a common ground. Fuel level gauges and senders work on units of resistance called ohms. If the gauge and sender are not matched in ohms then a false reading will be the result. To see if your gauge and sender are compatible you must check the ohms your sender shows at both full and empty. If these specifications do not match those of the gauge (listed below) then the two are not compatible. At that point you will either need to find a gauge to match your sender or a sender to match your gauge.
Gauge # …Ohms at empty …Ohms at full
7381…………73Ω………………………10Ω
7382 …………0Ω………………………90Ω
7383 ……240Ω…………………………33Ω "

According to these part numbers, NONE are compatible with Ford gauges or our sending units. Our gauges range from 100Ω when empty to 10Ω when full. There is nothing wrong with your wiring. BTW, it's impossible to wire our gauges backwards. Ford gauges, sending units and CVRs were manufactured by King-Seeley for many decades. - Dave

[1lobird]

Thanks for the responses guys! I guess I never went that far into the research! I just initally figured the whole system was shot. My tbird was a donor so everything was torn out of the instrument panel. It took me a few weeks and replacement parts to put back together, everything eventually worked except the left cluster gauge of the temp and the fuel. I cross referenced the diagrams and I found the sending unit was deteriorated with age. Replacing that I figured it was good. Nothing! So I bought the new gauge. Again I never looked this far into the power source I just figured it was something simple I was missing. Turns out it's much bigger! Lol thanks again for the feed back. I'll work something out with it.

[simplyconnected]

Whoa, Cowboy… I'm not convinced your gauges are broken and you did not test them. The answer is not to throw new parts at a problem but to use sound troubleshooting techniques to prove things are bad or good, first.

Send your new gauge back for a refund. You can't use it.

Do you have a 12-volt test light? Connect one end to ground. I assume you have your CVR connected. Turn your key on and check the CVR for power. If you got a mechanical CVR, one side should show a solid light. The other terminal will flash with regularity. Now move to your gauge. The CVR is connected to both Temp and Fuel gauges. Test the power side for a pulsing test light. If so, GROUND the other gauge post and watch the needle. Both gauges are identical so do one, watch the needle, then do the other.

Tell me what happened... Notice that the only tools required are a test light and a jumper wire with alligator clips. A typical 12-volt test light uses a small flashlight-type (or dash light) bulb, NOT an LED. - Dave

[1lobird]

Sorry, maybe I phrased that wrong. Let me correct myself and explain in complete detail; I'm one to take my time and know when the problem is fixable before I go with a different direction. I spent a great deal of time in the instrument panel to the steering column etc. plugging wires and sockets where they belonged. I got everything working up to that cluster. I did do a light test on everything, originally the two needles never moved anyway but they both got power and were grounded correctly. at this point I was frustrated and done not knowing how much gas I really had in the tank, I even stalled out cause I ran out of gas. I just settled for this equus cause I was 300% done messing with it. I could never find thee original cluster replacement online and the closest junk yard with a Tibrd donor to Tucson was in Maricopa and they charged 300 for it which I thought was ridiculous for a used one sitting in the Arizona sun. if you have any suggestions as to where I can find a new cluster or even a better gauge to mount in place of this equus one. I'd appreciate it. I honestly believe this cluster is shot. I am a persistent person, I wouldnt throw in the towel on this as soon as you give me credit for friend. haha

[YellowRose]

Fuel gauge reading backwards on a 62

Adrian, there are three companies I would contact come Monday, if you are looking for replacement parts. One is the Bird House, in Delaware, the Bird Nest in Oregon, and Thunderbird Ranch. All three are listed in the Advertisements Forum. They all three have used Tbird parts, off their parts cars and one of them might have just what you are looking for..

[jopizz]

Have you tried the Thunderbird Connection in Phoenix. They have tons of new and used Thunderbird parts. I'm sure they would have a used fuel/temp gauge for a lot less than $300.

http://www.thunderbirdconn.com/index.html

John

[simplyconnected]

Adrian, you've come to the right place. All of us want to see you save money, not throw it away on 'stuff' that doesn't work.

Ray and John give excellent suggestions for buying original gauges. There are repair shops, too. When your dash looks bone stock and works well, it is a very handsome display. None of the aftermarket gauges come close in looks or function. Setting them up electrically is not a big challenge so don't let it intimidate you. Ford gauges cannot be connected backward because they work by using the heat from current. There are no magnetic motors or armatures, either. It's a simple setup that is nearly bulletproof. If you have gauges that are burned out I can hardly believe it. The only failures I've seen are dashboards that were left outside in the rain for decades, all rusted and frozen.

eBay sells your whole 3-pod cluster for $350 obo with free shipping so you know the left pod is a lot cheaper than that. - Dave