Fuel tank gallons? Need help
Thread Starter
Racer
Joined: Jan 2008
Posts: 299
Likes: 4
From: Surprise AZ
Fuel tank gallons? Need help
Need help, On a 69 corvette when I add 4 or 5 gallons to the tank it reads full, then slowly goes down as I use it. Right now I have 1/4 tank, showing 4 inches of fuel with a yard stick. Does anyone know about how many gallons are left in the tank? I could use any kind of help, thanks
Thread Starter
Racer
Joined: Jan 2008
Posts: 299
Likes: 4
From: Surprise AZ
Not sure what you are showing me. I need to know how many gallons are in my tank. w/4 inches showing on my yard stick. Can you measure how many inches of fuel are in your tank, w/the gauge showing 1/4 tank. Thanks
Le Mans Master
Joined: Aug 2017
Posts: 8,336
Likes: 2,810
From: Cool Northern Michigan
You would have better luck with a Lottory Ticket than finding someone with a quarter tank and the correct year of tank.
You need an Ohm Meter. Somethings not right with the sender.
All gauges will read "dead" when no power is available.
Most gauges will read too high with power, but poor ground.
It's a perfect GRD and resistance that brings the gauge needle down into perspective measurements.
Maybe someone will chime in with what your Ohms should read with IGN switch on and less than 1/2 tank.
You need an Ohm Meter. Somethings not right with the sender.
All gauges will read "dead" when no power is available.
Most gauges will read too high with power, but poor ground.
It's a perfect GRD and resistance that brings the gauge needle down into perspective measurements.
Maybe someone will chime in with what your Ohms should read with IGN switch on and less than 1/2 tank.
Is my vette stock?? HAHA
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From: Im not allowed to tell you
2020 C3 of the Year Finalist - Modified
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you have to do it the hard way like I did.....pull the fuel pump supply line and drain your tank. Fill one gallon jugs and pour it in and measure it. 4 inches is only going to mean something to you becasue of your actual suspension setting, tires, and if you are parked on a totally level surface and the fact that the bottom of your tank is inclined, not flat. If you want to get your tank to read correctly with your gauge its about the only way to do it and get a very expensive fuel gauge calibrator
https://www.summitracing.com/parts/cin-sn34
I use this and my tank when it just hits empty has about 2 gallons in it....mine reads full fo r a while before it drops because you bury the float in fuel for a bit with the older bottom sensor tanks.
Do not use a gauge calibrator like Wilcox's variable resistor for the temp gauge. We tried it , it gets very hot and isnt accurate with the fuel gauge
https://www.summitracing.com/parts/cin-sn34
I use this and my tank when it just hits empty has about 2 gallons in it....mine reads full fo r a while before it drops because you bury the float in fuel for a bit with the older bottom sensor tanks.
Do not use a gauge calibrator like Wilcox's variable resistor for the temp gauge. We tried it , it gets very hot and isnt accurate with the fuel gauge
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Michael S. Palmer
Race Director
Joined: Mar 2017
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From: Virginia
Have a drywall bucket ready. Drain the tank. If it overflows, you had more than 5 gallons left in the tank.
The tank is not flat on the bottom. If you know where the tank is 4" deep, you can drop your spare tire, roughly measure the wet volume, and do some math. 231 cubic inches is about one gallon.
The tank is not flat on the bottom. If you know where the tank is 4" deep, you can drop your spare tire, roughly measure the wet volume, and do some math. 231 cubic inches is about one gallon.
2026 Loser of the Year
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From: New Or-leens Loo-z-anna
You members probably know the old school trick of bending the float arm slightly so the tank still has 3 gallons remaining when the (accurate) gauge needle just "touches" the E mark.
It gives you 30-40 miles of drive time to reach a gas station or Rest Area.
It gives you 30-40 miles of drive time to reach a gas station or Rest Area.
Le Mans Master
Joined: Aug 2017
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From: Cool Northern Michigan
Pushing that damn car up to the pump with still 1/8 tank showing was not my fun & joy.
Race Director
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From: Cottonwood AZ
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Need help, On a 69 corvette when I add 4 or 5 gallons to the tank it reads full, then slowly goes down as I use it. Right now I have 1/4 tank, showing 4 inches of fuel with a yard stick. Does anyone know about how many gallons are left in the tank? I could use any kind of help, thanks
If you are trying to determine how much gas you have before you are truly empty just drive it until you run out and have a premeasured can with you so you can get back to a gas station to fill up to determine what your car really holds.
Racer
Joined: Jul 2018
Posts: 331
Likes: 123
From: Sandusky, OH
And if you don’t want to wade thru the BS all the time, fix the wires and/ or change the sending unit and be done with it….
Steve O.
Pro
Joined: Aug 2000
Posts: 611
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From: Vancouver B.C.
On my 72, when my gauge reads E I have about 3 gallons. Never used yardstick to measure. But it’s around 4”.
