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on the Internet for over 30 years! and not clogged down with Ads! Again, thanks! | | | | Joined: Mar 2012 Posts: 240 'Bolter | | 'Bolter Joined: Mar 2012 Posts: 240 | I have a '47 3100. My oldest brother bought it in '84 and sold it to me in '98. The fuel gage has always read "E". I changed the sender some time back (when putting new wood in the bed), but it still reads "E". The truck came with a spare gage cluster that I've held off installing. If its any help, the gage always "bounces" off "E" when the key is turned on.
I've seen several posts indicating that a bad ground reads "F". Does the "E" suggest a common problem?
Thanks.
1947 3100 Advanced Design
Never, never, never, never give up. - Churchill | | | | | Joined: Mar 2005 Posts: 1,636 'Bolter | | 'Bolter Joined: Mar 2005 Posts: 1,636 | One side of the gauge is fed power when the ignition switch is turned on. See if it has power when the switch is on. If it does, it could be the wire from the gauge to the sending unit is shorted to ground making it read empty all the time.
Last edited by Roy Rodgers; 05/15/2012 6:51 PM.
| | | | | Joined: Mar 2011 Posts: 457 Shop Shark | | Shop Shark Joined: Mar 2011 Posts: 457 | Agree with Roy, those sender wires are notorious for shorting out, as the wire covering decays and the grommet going though metal deteriorates. Good luck!
1940 Chevy 1/2 ton pickup "KC" A day without sunshine is like, well, ..... dark! | | | | | Joined: Oct 2010 Posts: 171 Wrench Fetcher | | Wrench Fetcher Joined: Oct 2010 Posts: 171 | Could be that the float ain't working......too heavy and sinks to the bottom. Pull the sending unit, after you do what Roy said above, hold the sending unit perpendicular to the ground-same as it is installed- make sure there is power to it and grounded as well, turn the key on and move the float up and down .....slowly- this will tell ya if its the sending unit float
....David
| | | | | Joined: Mar 2007 Posts: 4,215 Moderator | | Moderator Joined: Mar 2007 Posts: 4,215 | I have the same problem, my float is made of cork. Interesting point about the float being a sinker. My wires are all brand new with good ground at the sending unit. I'll have to check it out. | | | | | Joined: Oct 2010 Posts: 171 Wrench Fetcher | | Wrench Fetcher Joined: Oct 2010 Posts: 171 | BDammer- Did you figure out the problem?
....David
| | | | | Joined: Jul 2008 Posts: 1,321 'Bolter | | 'Bolter Joined: Jul 2008 Posts: 1,321 | BD, I have had success with the following test. Fuel Gauge Test Usually when a fuel gauge on these old trucks goes past full and stays it's because the ground is bad. Could simply be a bad connection, or could be a bad sender. May also have a bad wire from the back of the gauge to the sender. One way to test that is to put a test light at the end where it connects to the tank. Disconnect the wire at the tank to test with the light.
If the wire is good, the test light will act as resistor and the fuel gauge should come back towards empty. You could just touch the wire to a ground, but you have to be careful you don't just hold it there or you could burn out the gauge.
Good luck, Harold
Harold Is a restoration ever finished? | | | | | Joined: Mar 2012 Posts: 240 'Bolter | | 'Bolter Joined: Mar 2012 Posts: 240 | Harold and David,
Thanks for the feedback. The big project this past weekend was getting the parking brakes back into adjustment so that I could take my [supportive, beautiful, eternally patient] wife for a ride in it for the first time in years. Grins all around the family, had my 14 year old son add another 4 gallons of gas "just to make sure".
I'm going to work on the fuel gage this weekend. If the wire is not bad, I'm guessing the gage is burned out and I'll put the replacement gage set in when my project gets to a good point for it.
I'm pretty sure the sender is okay since I replaced it some time ago and no symptoms changed.
Best regards,
Bill
Last edited by BDammers47; 05/24/2012 5:26 PM.
1947 3100 Advanced Design
Never, never, never, never give up. - Churchill | | | | | Joined: Apr 2012 Posts: 27 New Guy | | New Guy Joined: Apr 2012 Posts: 27 | I've got a similiar problem, it's always about 1/2 full. I was thinking the float was bad.
It's not the weight of the load, that breaks your back. It's how you carry it.
| | | | | Joined: Mar 2012 Posts: 240 'Bolter | | 'Bolter Joined: Mar 2012 Posts: 240 | Gents,
I finally got to the fuel gage. It's wired oddly: There are two wires to the hot lead in and two wires on the sending unit terminal.
I assume that the two wires on the hot side are an old "excuse for a splice" - I haven't had a chance to trace them both back.
The two wires on the sender side are (1) the sender and (2) a connection to a terminal on the steering column.
I disconnected the wire to the steering column: no change in the gage reading and the horn still worked.
I may stop at this point and re-wire the truck (I bought a new harness when I planned the rebuild). If the issues persist with the wiring restored, I'll troubleshoot the gage some more.
Thanks,
Bill
1947 3100 Advanced Design
Never, never, never, never give up. - Churchill | | | | | Joined: Jun 2010 Posts: 298 'Bolter | | 'Bolter Joined: Jun 2010 Posts: 298 | i have the same problem,i tested it this weekend, test wire on sender and lites up ,when you put wire touch to ground the gauge trys to move just a bit. do not know what the problem is,any help out there? | | |
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