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| | | Forums66 Topics128,146 Posts1,056,795 Members48,454 | | Most Online14,466 Apr 26th, 2026 | | AD Chevy Trucks Over 6,000 pictures Brad Allen has an awesome collection of Chevrolet factory pictures that he has set up from film strips. Check them out!
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on the Internet for over 30 years! and not clogged down with Ads! Again, thanks! | | | | Joined: Aug 2005 Posts: 16 'Bolter | | 'Bolter Joined: Aug 2005 Posts: 16 | The gas gauge stopped working on my 1961 and is pegged past full whether ignition is off or on. I removed the sending unit from the tank and all looked good. Connected it externally and moved the arm up and down and nothing happened with the gauge. Reinstalled and made sure both the ground wire and sending wire were clean and secure. I don't have an electrical tester. All the other gauges are working. Any thoughts about how to proceed would be appreciated.
Last edited by Phillip; 02/08/2021 3:49 PM.
| | | | | Joined: Jun 2011 Posts: 5,096 Crusing in the Passing Lane | | Crusing in the Passing Lane Joined: Jun 2011 Posts: 5,096 | Buy a VOM meter and learn how to use it, they are cheap. Then check the input side of the gauge and ground.
Ed
'37 GMC T-18 w/ DD 4-53T, RTO-610, 6231 aux., '95 GMC running gear, full disc brakes, power steering, 22.5 wheels and tires. '47 GMC 1 ton w/ 302, NP-540, 4wd, full width Blazer front axle. '54 GMC 630 w/ 503 gasser, 5 speed, ex fire truck, shortened WB 4', install 8' bed. '55 GMC 370 w/270, 420 4 speed, grain, dump bed truck from ND. Works OK.
| | | | | Joined: Aug 2005 Posts: 16 'Bolter | | 'Bolter Joined: Aug 2005 Posts: 16 | Sorry bout that double posting. I decided I posted in the wrong on and didn't see how to delete the first one. | | | | | Joined: Aug 2005 Posts: 16 'Bolter | | 'Bolter Joined: Aug 2005 Posts: 16 | Thanks Ed. I just purchased one and will try to figure out what to do with it. | | | | | Joined: May 2007 Posts: 1,718 Moderator: 60-66 Trucks; North Eastern Bolters | | Moderator: 60-66 Trucks; North Eastern Bolters Joined: May 2007 Posts: 1,718 | I took care of the duplicate post. No worries. | | | | | Joined: May 2005 Posts: 8,983 Sir Searchalot | | Sir Searchalot Joined: May 2005 Posts: 8,983 | 1. Don't put the sender back in until gauge works. It is THE tool you need for bench testing. 2. You say you connected it externally and nothing happened. That would depend on how you "connected" it/tested it. 3. If you are unsure or not acquainted with electrics, Don't hook anything up until you get instructions here. You will damage something. Watch the vid and read the link to get up to speed. ClickAnd ClackAsk further after reviewing, or report results. It is going to be a ground problem or the gauge or the sender. Does not matter if they "look" good.
Right is right, even if everyone is against it, and wrong is wrong, even if everyone is for it. - William Penn | | | | | Joined: Mar 2014 Posts: 4,504 Moderator, Electrical Bay | | Moderator, Electrical Bay Joined: Mar 2014 Posts: 4,504 | On your 1961 it is very easy. When the float is at the bottom, the ohm reading should be close to 0 (choose 0-200 ohms on your meter or just ohms if your meter auto-selects the range). When the float is at the top, the ohm reading should be 30 or close to that. As you move the arm slowly while the meter is connected (one lead goes to a good ground source or the body of the sender unit and one lead goes to the center screw where the fuel gauge wire connects) the reading should range between 0 and 30 ohms. Ohms as you may already know are units of resistance. Please let us know if you have questions.
If you know any friends who are electronics hobby-type guys or gals, ask them for a 10, 15 or 22 ohm resistor. Those are crazy common and anyone who tinkers with circuits ought to have several around. Then it becomes really easy. Remove the center nut on the sender, remove the wire and with the ignition in the on position, hold one side of the resistor to the connector of the wire and ground the other end of that resistor. Don't worry...you won't get any sort of shock. If you have a 10 ohm resistor, your fuel gauge should read about 1/3 full. A 15 ohm resistor should give you about 1/2 tank reading and a 22 ohm resistor should give you about 2/3 tank full reading. If that doesn't happen, and if your sender seems to be working (incredibly unlikely if you have the original sender), then something has happened between the tank and the gauge.
~ Jon 1952 1/2 ton with 1959 235 | T5 with 3.07 rear end
| | | | | Joined: Mar 2014 Posts: 4,504 Moderator, Electrical Bay | | Moderator, Electrical Bay Joined: Mar 2014 Posts: 4,504 | If you want more on fuel sender units, I've been posting lots of notes and observations here recently...including work done on rebuilding/rescuing an OEM sender unit. You should not have to look far to find them.
~ Jon 1952 1/2 ton with 1959 235 | T5 with 3.07 rear end
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