The Ford Barn

johcol · 08-31-2021, 11:08 AM

Hello! Working on a friends truck. He has re wired the truck and changed it to twelve volts. A voltage reducer is used to drop the voltage to the original gauges. The oil pressure works fine, however the temperature as well as the fuel do not. With key on ,temp gauge will bury itself below cold and fuel gauge stays on empty .( If you ground the sensor wire, it will go to full.) Checked voltage at gauges (6.4 ) and ground at fuel sending unit. Temperature sender resistance is approx.. 1.5 ohms cold. Any help appreciated.

JSeery · 08-31-2021, 04:14 PM

Did the gauges work correctly before the change to 12v? The voltage reducer should take care of the voltage to the gauges, and if they worked on 6v, they should work fine on 12v (with the reducer). Is the temperature sending unit an original? If so, an ohms reading would be fairly meaningless. They work on current pulse, not resistance. If it has been switched to a resistance unit, I have no idea, but there may be a difference between 6v units and 12v units?? Again, no idea on that one.

johcol · 09-01-2021, 04:12 AM

Will check and see if sender (temp) is correct. When fuel sender is grounded, gauge will respond to full .
Thanks Again!

FortyNiner · 09-01-2021, 06:26 AM

Is the fuel sender the original factory version?

chriscris · 09-02-2021, 11:53 AM

The steel bus bars on the back of the cluster that tie together the 3 gauges nees to be removed, or swapped to other terminal, if not already done

JSeery · 09-02-2021, 11:57 AM

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Quote:

Originally Posted by chriscris

The steel bus bars on the back of the cluster that tie together the 3 gauges nees to be removed, or swapped to other terminal, if not already done

Why would that be? Gauges shouldn't care about + vs - ground.

08-31-2021, 11:08 AM	#1
johcol Junior Member Join Date: Apr 2018 Location: New Jersey Posts: 4	1950 FI Gauge Conversion Hello! Working on a friends truck. He has re wired the truck and changed it to twelve volts. A voltage reducer is used to drop the voltage to the original gauges. The oil pressure works fine, however the temperature as well as the fuel do not. With key on ,temp gauge will bury itself below cold and fuel gauge stays on empty .( If you ground the sensor wire, it will go to full.) Checked voltage at gauges (6.4 ) and ground at fuel sending unit. Temperature sender resistance is approx.. 1.5 ohms cold. Any help appreciated.

08-31-2021, 04:14 PM	#2
JSeery Member Emeritus Join Date: Nov 2012 Location: Wichita KS Posts: 16,132	Re: 1950 FI Gauge Conversion Did the gauges work correctly before the change to 12v? The voltage reducer should take care of the voltage to the gauges, and if they worked on 6v, they should work fine on 12v (with the reducer). Is the temperature sending unit an original? If so, an ohms reading would be fairly meaningless. They work on current pulse, not resistance. If it has been switched to a resistance unit, I have no idea, but there may be a difference between 6v units and 12v units?? Again, no idea on that one.

09-01-2021, 04:12 AM	#3
johcol Junior Member Join Date: Apr 2018 Location: New Jersey Posts: 4	Re: 1950 FI Gauge Conversion Will check and see if sender (temp) is correct. When fuel sender is grounded, gauge will respond to full . Thanks Again!

09-01-2021, 06:26 AM	#4
FortyNiner Senior Member Join Date: May 2012 Location: u-rah-rah-Wisconsin Posts: 1,137	Re: 1950 FI Gauge Conversion Is the fuel sender the original factory version? __________________ 19 and 49 F1 - jes' like Henry II built 1946 Deluxe - as Henry built it

09-02-2021, 11:53 AM	#5
chriscris Junior Member Join Date: Feb 2011 Location: Campbellville, Ontario Posts: 15	Re: 1950 FI Gauge Conversion The steel bus bars on the back of the cluster that tie together the 3 gauges nees to be removed, or swapped to other terminal, if not already done