My 86 F250 carbureted 351W truck's gas gauge doesn't work. Can anyone tell me how to test my gauge to make sure that it works? and how to tell if the problem is in the tanks or the dash cluster? or maybe the fuel tank selector switch in the dash causing a problem??

 

Ground the wire that goes to the sending unit and the gauge, with the key on, should go to Full.

 

There are 2 wires going to it, a black wire and a black wire with a yellow stripe. Which one's the ground? me and my dad tried that tonight but the gauge didn't do diddly squat.

 

Black is ground, so you need to ground the other one.

 

Okay so I need to ground the one with the yellow stripe on it? I wanna make 100% sure so I don't wind up frying something lol.

 

Yes, but since black is ground you just connect those two wires.

 

Alright now if my problem is in the tanks, are the sending units rebuild-able or not? I see new ones at the auto parts stores for like $80

 

That would work - connect the two wires - or, you can connect the yellow/black wire direct to the frame (assuming you can find a clean, good ground on it).

 

I'm running a super long wire up to a clean spot on the engine bay, I can't find a clean enough spot under the truck

 

No, the sending units are not rebuildable.

 

Not generally fixable.

My own experience leads me to stay away from Spectra Premium sending units; I have 3 of them, they don't last more than 2-3 years before they start wiggin' out.

When I can afford it, I want to get OEM replacements (look how long they last!).

 

The problem I'm having right now is I can't seem to find a auto parts store that sells them, Autozone doesn't have anything listed, Ogehtto auto parts has nothing listed for them. Where the heck can I find these things, especially the OEM ones?

 

Perhaps Gary or Kevin can look tonight (we all have the FoMoCo 1980/89 Light Truck Parts catalog) but I'm going to bed right now. Somebody remind me tomorrow if need be.

I think 9H307 = sender + pump, I think just the sender is a 9242 or something similar.

 

Gary went to bed ahead of you, apparently. Browsing the illustrations we need to determine which tank it is: aft-axle or mid-ship? And, we need to know the wheelbase of the truck, which is shown on the Cert Label on the door post. Also, what is the GVWR on the truck. All of these questions are needed to determine which part # is needed. Sorry.

 

Hmmm...if you're going to be rooting around the parts catalog anyway, any chance you'd be willing to look mine up as well? I'm getting ready to do my tank, and it would be great if I could get an OEM sender:

1980 F-150, 300 engine. 133" wheelbase, 5450 GVWR. Should be the 19 gallon midship tank.