I have a 1972 F-100. There is a pigtale connected to nothing under the hood which originates from the dash area. Does anyone know if that is the wires to the gages?

Thanks,

Tony in New Mexico

 

Should not have anything to do with the fuel gauges. They go to the gas tank sending units.

If they come from the engine bay to the dash area, they could be oil pressure, temperature or alternator.

 

Do you see it here?

 

Dear Dennis,

Thanks, but no I don't see it on the pic. The wires I found are under the hood, but originate from beneath the dash. The one wire in paritcular is white and is the only one in that is hot.

None of my gauges work. There is an aftermarket temp gauge that does work. I was in hopes of finding the wire that would bring the orginal fuel gage back to life, but so far no luck.

Thanks,

Tony in new Mexico

 

Is it below the m/cylinder in that general area? If so, I have the same plug but never traced it back to it's orgin. My truck is a 69 Ranger. Came with the big block, drum brakes and no power steering from the factory but as been upgraded to a modern pro street truck. Maybe I'll research and see what this plug was for.

Tony in North Carolina
stroker393
new pics coming soon; burn-outs too!

 

I notice in the picture that the fuel gauge has two bolts that seem to connect to the "printed circuit". Would those bolts be the posts that wires from the sending unit hook into? If I ran a wire from the sending unit to those bolts, would my gas gauge work?

Tony in New Mexico

 

Dear Tony in NC,

Yes, that is the wires to which I refer. They come out of a hole in the fire wall and started from a bundle in the dash. Unfortunately, I can't see what they connect to from there. I presume that the plug that fits into the back of the cluster connects those wires to the various gauges via the "printed circuit".

BTW, I used to be a church music director in Siler City NC. Do you know of that town???

Tony in New Mexico.

 

Siler city; near Pittsboro and Asheboro, right? Haven't been that way in awhile but talk to friends nearby. Looking at your past posts you have fuel problems as in gauge not reading and setting on empty, right? If that's your problem pull the sending unit from the tank and I bet the brass float is full of fuel - replace it and your problems are over.

Tony in N.C.

 

Dear Tony in NC,

The problem may be the float, but there are no wires running to the sending unit. That is why I've been on teh quest to trace the wires from the gauge. I was in hopes of getting the orginal to work again.

If I find the wires and get them connected to the sending unit, it still may not work due to the float which may be why hte last owner disconneted them.

Keep the advice flowing.

Tony in New Mexico

 

My 69 has a orange and black wire coming out of the dash and running up the door pillar area to the gauge; orange to center of unit and black to ground. Check in that open area behind the door and seat and you may get lucky.

 

Ok here is the deal.

The Fuel Tank sender has two wires coming from it. Black and orange (as previously stated.) The black goes to ground. The orange goes up and over the door and back down the A-Pillar. Then comes through the sidewall by means of a hole. Then it goes to a bullet type connector. The output of this connector is still orange. It then goes to a connector on the left hand side of the truck under the dash. From here another orange wire is piggy backed off of it (on the same side of the connector) and goes to the instrument cluster connector. From there it goes to the gauge or PWB (Depending on year model). Now back at the connector under the dash. The other side of the connector has another orange wire that goes through the fire wall and into the engine bay to a bullet connector. If you have dual tanks the second sender will connect here. If you have single tanks this wire hangs unconnected in the engine compartment.

Years of age and heat can cause the insulation on these wires to change colors. Try to peel back some of the wire loom to get the true color. What you see as white may very well be orange.

 

Thanks to all you guys!

I appreciate the help you have all been. I will let you all know how it turns out.

Tony in New Mexico

 

Dear gang,

I gave getting the gas gauge to work another try the other day. I made some progress, but still not exactly right. Here's what I did.

I removed the cluster and found that they printed curcuit on the back was damaged. The power to the gas gauge was cut off. So I wired a black and red wire to the posts on the cluster's gas gauge. Ran that wire to the tank sending unit. Since the original orange wire seemed to not have any current, I barrowed a wire from under the hood that went no where, but was hot.

I sent that wire through one side of the post, hooked the black wire out the other post and to the fuel tank. rather I ground it or not, I still get a reading of full. I'm sure it isn't full at all.

I suspect that it may be the sending unity is bad, or the float is stuck. I would think, however, if that were the case, the gauge would read empty.

Any thoughts on this? I would also like to know where I might get another sending unit.

Thanks,

Tony in NEw Mexico.

 

I once tried to install a sending unit in one of my saddle tanks with a auto parts store copy, but it would not work with dash gauge. Was told it was different because of the ohms, package said I had to use same manufacturers after market gauge. Didn't do it, so will look up Ford sending unit at salvage yard or dealer if available.

 

As far as resistance, Ford and Chrysler are the same but GM and Stewart Warner are different.

Ford/Chrysler: Full 0-10 ohms / Empty 70-73 ohms
General Motors: Full 0-10 ohms / Empty 91-93 ohms
Stewart Warner: Full 29-33 ohms / Empty 244-250 ohms