In my 48 F1 I have updated the inst cluster with a voltage regulator and original gauges have been changed on backside of gage to 12 volt. (Tuck engine installed is 302/ 12 volt) I am updating the fuel sending unit and attempting to find out if sending unit should be 6 volt or 12. The volt regulator drops the voltage to 5.5 volts/ I am told 12 volts would burn out gage. My question is which sending unit should I get 6 or 12 volt? I suspect it would not matter-Thanks for any info shared
hmmm..i don't have an exact answer for you.. i will look around..let me put out some theory on how it works.. first.. electrons flow from negative to positive.fords were positive ground until the 1956 models... is your truck still wired positive ground?? there are more things to think about when performing a 6 volts positive ground to 12 volt negative ground systems..use your OHM meter and check the resistance of the fuel sending unit when the float is in the full position and when its in the EMPTY position.. write these down..then slowly move it full range.. the ohm meter should either increase or decrease resistance steadily... without any dropouts or spikes.. this proves that the sending unit is good... it still has to contact the fuel tank.. and the tank needs to be grounded to the body.. i ill come back and post more tomorrow.. its really late.. or early..
It is a negative ground/ truck updated with 79 302 engine with 12 volt system / When I get some time and temp warms up I will continue on. I understand that the sending unit works on increase / decrease resistance. But with the voltage regulator installed on back of inst cluster dropping the volts output to gages to 5.5 volts/ backside of gages changed to 12 volt setup. I suspect original sending unit is installed/ which was for 6 volt system/ Witch may be the entire problem.Thanks for your input/ I will update when I have a outcome/ Time restricts me from working on my Truck/ I may not get back to it for couple of weeks.
Finally had some time / replaced the wire from the sending unit to the gage and it works. Did not have to replace sending unitThanks for inputs