Location of fuel sending unit wiring 73 F250

[moparmusclecars]

Can anyone help me figure out the color of the wire I should be looking for under the dash? I think it may be orange, but not sure. Also on a 73 I would think it runs under the mat (or carpet) back to the inside of cab tank. Can anyone help me out on this? Maybe 73 and 74 is the same? I am guessing it would just be a single wire for the fuel tank sending unit. Does anyone have an extra that they would sell if I can't find mine? It appears to be missing (unplugged).

 

[Mil1ion]

It is bundled with the main harness that exits on the firewall then runs down the frame driver's side to the SU's

shown here

 

[moparmusclecars]

why would it run down the frame and out of the firewall on a truck with INSIDE cab fuel tank? just curious. I assumed it would run across the floor and plug into my sending unit.

 

[Mil1ion]

sorry wrong illustration.

I'll go find the in cab tank
They don't usually run a wire under the carpet, if anywhere it would run under the door sill plate away from foot travel.

 

[BuzzGun79]

well i dont mean to bust in on someone elses thread,but since were on the subject.i also wil need to find the feed wires to the cluster gas guage on my 79 f 250 since they were cut.the main tank is under the bed behind the cab & i believe the rear was an add on.there is a selenoid under the truck to switch the tanks but has been disconected along with the rear tank & plugged off.there is also a selector switch next to the heater control,but no wiring provisions to hook it up.at this point i just want to get the gas guage working off the main tank.will worry about the external & wiring up the selenoid at another time,as these tanks are huge & i really dont need the rear as of yet since it will be put away shortly for winter.again many thanks!!...Bob

 

[Mil1ion]

The Main tank is between the frame rails at the the rear.The Mid-ship tank is also known as the AUX tank

also, the word is Solenoid not selenoid

 

[BuzzGun79]

All righty then,i guess my next question would be, why there is no wiring harness to support both tanks in the dash..the heater & tank switch have very simular plugs..there is only 1 plug in the harness, its is for the heater.there is no pigtail coming off the harness to feed the tank selector switch.that i can find & i dont see anything that may have been cut off the harness.hmmm.thanks for the clarification of the tanks & spelling...lol right now im running off the aux tank then. cant figure out what this previous owner was trying to do.cut off the cluster plug...now this..lol. there are wires going to the sending unit of the aux tank sending unit..but not the rear or the soleniod hmm.cant figure out what this previous owner was trying to do.also the rear tank has the wrong filler neck in it,which made me think it was added later. i just hate it when some hack up wiring on a decent rig such as this one is.any suggestions? thanks Bob

 

[Mil1ion]

We read about people that thought they were smarter than Ford all the time by cutting and splicing wiring harnesses.
The usual reason for cluster wiring is because they thought they could swap from warning lights to gauges without any issues

 

[BuzzGun79]

I hear ya Mil1on..but in my opinion even the guage clusters are electricly operated from electrical sending units {oil press. coolant temp}if he wanted guages why not go mechanical this is what i did,i think they are much more reliable, accurate than electric...but that is me.any clues on my tank & dash wiring issues.the solenoid is mounted under the bed{and appears to be new} not near the frame rail as the diagram above shows.or more than likely im going to have to start from scratch...just great {little sarcasm there} I wish you were in Ohio right now..lol..Bob

 

[moparmusclecars]

wow! I guess my very first posting here got hi-jacked! Hopefully, my original question(s) someone can still help me with.

 

[BuzzGun79]

i meant no disrespect mopar our dash issues as far as finding the feed wires for the fuel guage are similar,but i have other major wiring issues as well & i was seeking some insight. im no electrician by any means & this is going to be a rough fix for me i will bow out now till i figure all this out,then start my own thread..again i appologize...Bob

 

[Mil1ion]

I do the best I can considering my health.


The wiring goes up the A-Pillar ACROSS THE TOP OF THE DOOR and down to the SU

 

[lostinfords]

Looks like red or orange??, I guess more orange,I just took this out of a 77 f250, also have the tank and sender available...pm me w/ contact info if this is what you need