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Discussion Starter · #1 ·
I am the proud new owner of an Ocre 1971 GTV(euro specs) that I bought from AlfaTom in Kitchener, Ontario. I can't believe how nice the car is. An issue he pointed out to me was the gas gauge not working properly. It's has a brand new gas tank. The gauge is always on E, but when you fill up the tank, the red "empty" light turns on. I've just read Farace's post on faulty gas gauges, amd will follow his steps unless someone knows a quick fix for it.
 

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It could be a bad gauge sender in the tank. I might just be a bad ground. Mine never shows the light, and at "E", it still has about 2 gal left. I have never seen the red light go on with fuel in the tank.

Will
 

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Could be a possible mismatch in the sender and the gauge. A Veglia gauge must have a Veglia sender; same with Jaeger.
Then again, it may as simple as reversing the two wires on the sender.
 

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I reversed the wires on my Veglia setup once, and it simply reversed the signal. A full tank indicated empty, and an empty tank indicated full.

To test, I simply removed the sender unit from the tank - connected it and moved the float up and down - while watching the guage through the rear window. What I love is that these units provide an instantaneous signal - unlike my Toyota which takes about 5 minutes to register a change in level.

There's no risk of spark, or these units wouldn't be inside the tank in the first place.

-Col-
 

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According to me there is a mismatch between the brand of the dashboard and the sender. I had the same problem in the past. Use the search function to find the thread about this
 

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Discussion Starter · #6 ·
Well I have to think it's the old mismatched sender/gauge syndrome. The gauge is definitely Veglia, but how do I tell the make of the sending unit? I have never posted a picture here before, so I'll describe the unit to the best of my ability. It's gold colored with the writing W0 01387, then a M (or W) and T at 12:00 and 6:00. There's a symbol that looks like a line with a U under and above it. Thanks
 

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Discussion Starter · #9 ·
I dug through all the receipts I got with the car and found out that the tank was purchased from EB Spares in the U.K. I've sent off an email to them to help me identify it.
 

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Discussion Starter · #10 ·
Well here is the email from EB Spares:

"the Euro cars have a tank sender with two connections.

one of the connections gives a perfect connection with no resistance when the float is at the top (full)
when the float moves down to empty it gives a resistance of approx 400ohms

the other connection is the warning light. when the float goes to approx 1/4 (empty) this then give a connection to illuminate the light. (on/off)

to test the sender you use an ohm meter. check the wiring on this unit is correct.
You may need to check it with the sender out of the tank.....

to test the gauge turn ignition on, and earth each wire out individually. one of the wires will illuminate the warning light, the other will take the gauge from below 0 up to max.

also make sure the unit is well earthed..."

Well I tested it and the terminal at the sending unit with the white w/grey stripe wire lights up the low fuel light when grounded. The purple wire when grounded does nothing to the gauge.
I even ran a separate wire from the purple wire terminal around car directly to the back of the gauge. The needle did not move.

I relayed this back to EB and they think the gauge is faulty. So I started looking online for a replacement and can't find one! I tried re-originals, Highwood, Centerline, International and I can't find a replacement. Any ideas to where I can find one, if you think the EB diagnosis is correct?
Thanks
 

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...one of the connections gives a perfect connection with no resistance when the float is at the top (full)
when the float moves down to empty it gives a resistance of approx 400ohms
Sounds like a Jaeger unit. The Veglia unit works opposite; low resistance at the bottom and high resistance at the top as evidenced by the pics here.

More later...
 

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check for 12 volts on one terminal on the guage any time the ign switch is on. also, the case of the guages must be grounded for the guage to work. my sons car had been repainted and the brackets that mount the guages hadnt grounded thru the new paint.
cliff
 

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Discussion Starter · #13 ·
I have to admit I'm a rookie with a multimeter but I am starting to think it's a grounding issue. The hood and interior courtesy lights don't work either. The PO replaced front and rear floor pans, spare tire compartment and gas tank. Then painted the whole underside with POR-15 and a few coats of paint. My neighbor is an electrical engineer and said he'll help track things down. I'll let you all know what the verdict is. Thanks for the help up to now!
 

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Discussion Starter · #14 ·
Well gang, here's the latest....
1. The tank is grounded
2. The gauge is grounded - see note below
3. When grounding out the terminals at the sender, the low fuel wire(white w/stripe) lights up the warning light. The purple wire does nothing
4. A continuity test on the purple wire shows it is not broken.
5. My friend said he grounded out the gauge and there was never any movement of the needle. I told him of the compatibilty issue of gauge and sender, but he said by grounding out the gauge it still should of registered because at that point the sending unit was out of the picture. So his thoughts are that the gauge is bad
6. I have not pulled the sender yet, it's something I hope I wouldn't have to do.

I am going to send this along to EB Spares and see what they think. But if my friend is correct, where can I get a replacement? And if I do, should it be a Jaeger?


Note: Late news!.....
When the black ground wire is disconnected from the gauge, the gauge case still shows a ground. So the gauge is grounding itself internally, hence a bad gauge? Using the wiring diagram that Papajam sent me, it shows that there should be only one ground(black wire)
 

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If you're getting battery voltage to the back of the gauge via the pink wire, then I'd have to conclude that the gauge is kaput.
 

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Discussion Starter · #17 ·
Revisiting the gauge issue

Jim, with the car in winter repair mode I pulled the fuel sending unit to test it against your photos. I'm not the greatest with a voltmeter but I think I got it right. Even though it looks like a generic sending unit, it acts like a veglia and should work my veglia gauge. Is this true? With the dash and consoles out, I'll start to track down the electricals to see if those are the culprits. Because even the replacement gauge I got from Andrew, acted oddly.

While I've got your attention, when I am ready to reinstall the dash and consoles...does the dash go in first or the console?

Thanks
 

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· Trained (ex)Professional, , 1953-2018 RIP
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It looks like the sender is working okay. So it would seem that leaves either the power wire to the gauge or the gauge itself.

I suppose that the dash and consoles could go in in any order but I always start with the dash. Then the gauge console with seat console going in last.
 
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