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| | | | Joined: Dec 2010 Posts: 50 'Bolter | | 'Bolter Joined: Dec 2010 Posts: 50 | I have a 1949 3100 that has been converted to 12v. I believe my gas gage is not working (just dumped 5 gallons of gas in it and the gage didn't move off of "E". I have read in the past to first check the ground on either the sender or gage but I have no idea how to do that. Simple instructions for an electrical dummy would be most appreciated. Thanks
Last edited by Peggy M; 06/07/2024 8:11 PM. Reason: added more info to the title
1949 3100
| | | | | Joined: Jan 2022 Posts: 2,481 'Bolter | | 'Bolter Joined: Jan 2022 Posts: 2,481 | There's a tech tip for that.
'57 GMC 102, Original 347 V8, HydraMatic, 3.08 rear gear, added A/C, disk front brakes, HEI, AFB carb, '98 Honda Black Currant paint. T-boned and totaled 10/12
'52 GMC 152 Stake Bed, Original 228, SM420, added A/C, HEI, disk front brakes, '67 Chev 3.55 rear gear. Gets used as a real truck.
| | | | | Joined: Dec 2010 Posts: 50 'Bolter | | 'Bolter Joined: Dec 2010 Posts: 50 | Bill thanks. One question…in point #3 it states to do a continuity test. What is that and how is it done?
1949 3100
| | | | | Joined: May 2015 Posts: 11,134 Housekeeping (Moderator) Making a Stovebolt Bed & Paint and Body Shop Forums | | Housekeeping (Moderator) Making a Stovebolt Bed & Paint and Body Shop Forums Joined: May 2015 Posts: 11,134 | A continuity test is where you check that a wire will carry current. It's usually done with a multimeter set on ohms and clipping the leads to each end of the wire. Good continuity will show zero-1 ohm on the meter. If the meter reads infinite ohms, then that indicates a break in the wire.
Kevin 1951 Chevy 3100 work truckFollow this saga in Project JournalPhotos 1929 Ford pickup restored from the ground up. | 1929 Ford Special Coupe (First car) Busting rust since the mid-60's If you're smart enough to take it apart, you darn well better be smart enough to put it back together. | | | | | Joined: Dec 2010 Posts: 50 'Bolter | | 'Bolter Joined: Dec 2010 Posts: 50 | Thanks. Is the ignition switch turned on to conduct this test?
1949 3100
| | | | | Joined: Apr 2008 Posts: 899 'Bolter | | 'Bolter Joined: Apr 2008 Posts: 899 | No power is applied for a continuity test.
Ed
| | | | | Joined: Dec 2010 Posts: 50 'Bolter | | 'Bolter Joined: Dec 2010 Posts: 50 |
1949 3100
| | | | | Joined: Jan 2022 Posts: 2,481 'Bolter | | 'Bolter Joined: Jan 2022 Posts: 2,481 | and to do the continuity test right at least one end of the wire needs to be disconnected. For instance, disconnect the wire from the sending unit.
'57 GMC 102, Original 347 V8, HydraMatic, 3.08 rear gear, added A/C, disk front brakes, HEI, AFB carb, '98 Honda Black Currant paint. T-boned and totaled 10/12
'52 GMC 152 Stake Bed, Original 228, SM420, added A/C, HEI, disk front brakes, '67 Chev 3.55 rear gear. Gets used as a real truck.
| | | | | Joined: Dec 2010 Posts: 50 'Bolter | | 'Bolter Joined: Dec 2010 Posts: 50 | Bill but the wire from the sending unit to the gas gage is longer then my test probs so how do I test that wire or do I just hook one prob up to the disconnected sender wire and the other to ground?
1949 3100
| | | | | Joined: Jan 2022 Posts: 2,481 'Bolter | | 'Bolter Joined: Jan 2022 Posts: 2,481 | You could add an additional piece of wire to the wire you removed from the sending unit to make it long enough to reach with your meter leads.
But before you go to a lot of trouble, what happened when you did the steps a,b & c of "testing the sending unit installed in the tank (key on)"?
'57 GMC 102, Original 347 V8, HydraMatic, 3.08 rear gear, added A/C, disk front brakes, HEI, AFB carb, '98 Honda Black Currant paint. T-boned and totaled 10/12
'52 GMC 152 Stake Bed, Original 228, SM420, added A/C, HEI, disk front brakes, '67 Chev 3.55 rear gear. Gets used as a real truck.
| | | | | Joined: Dec 2010 Posts: 50 'Bolter | | 'Bolter Joined: Dec 2010 Posts: 50 | Bill my truck is in storage about an hour away. Hopefully I can get to it later next week. I just wanted to get as much information before I tried to tackle the problem.
1949 3100
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