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| | | | Joined: Mar 2005 Posts: 627 'Bolter | | 'Bolter Joined: Mar 2005 Posts: 627 | Can I simply swap the wires on the 2 gauge terminals?
Needle moves very slightly when ignition is on, drops when it is off. Tank should be about 1/3 full.
My ammeter works backwards but provides the necessary information.
Mike Barnes
1950 GMC 1-ton pickup
| | | | | Joined: Mar 2005 Posts: 627 'Bolter | | 'Bolter Joined: Mar 2005 Posts: 627 | Gauge reads full with key on when the sending unit wire is removed.
Mike Barnes
1950 GMC 1-ton pickup
| | | | | Joined: Mar 2005 Posts: 627 'Bolter | | 'Bolter Joined: Mar 2005 Posts: 627 | I found the gauge works as it is, no need to swap the wires. Also found my new sending unit float is full of fuel!
Mike Barnes
1950 GMC 1-ton pickup
| | | | | Joined: Mar 2005 Posts: 627 'Bolter | | 'Bolter Joined: Mar 2005 Posts: 627 | Sending unit and gauge works, just have a split in the float.
Info that may help others with a 6v system: with sending unit wire removed you get 30 ohm from the wire to ground. With the same connection you get 3v with the ignition switch on. As stated elsewhere, sending unit reads 0 ohm with empty tank and 30 ohm with full tank.
Mike Barnes
1950 GMC 1-ton pickup
| | | | | Joined: Jul 2000 Posts: 2,192 Insomniac | | Insomniac Joined: Jul 2000 Posts: 2,192 | Don't forget fuel gauge voltage reducer when switching from 6 to 12 v.
Gord 🇨🇦
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1954 1/2 ton 235 4 speed
| | | | | Joined: Jun 2011 Posts: 5,096 Crusing in the Passing Lane | | Crusing in the Passing Lane Joined: Jun 2011 Posts: 5,096 | Might as well switch the ammeter wires to get correct reading, less confusing.
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.
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