Wireing for Auxilury Tanks

[Jimbo]

I pulled the canopy off of the truck and found 3 wires tha was coming in from the side. One wire is orange, one brown and one a light tan color could those be the ones for the tanks. The main tank inside the cab is orange with a black going to ground. Thanks for the info. Have not orderd the wire manual yet waiting for payday. Jimbo

[68F250]

Ok I finally found the wiring diagrams!

Orange is the color of the wire for the stock aux. tank and is also the color for the in-cab tank too.

The only brown wire I see is for the tail and licence plate lamps.

I don't see a light tan wire anywhere.

Do these wires look stock or added in? Can you tell where they originate?

[Jimbo]

Sorry about that I hit a wrong key. I just got a wireing diagram manual from Jim Osborn Repoductions inc. It does not show for 2 aux tanks. I am not sure how to get to the top of the tank to see where the ground wire is suppose to be hooked up to. Do you have any Ideas how to wire a switch in so I can run it off the stock gage? Thanks for the help. Jimbo

[68F250]

Yes, three tanks won't show up in the wiring diagrams because it's a custom job. A single switch for that is not simple but you should be able to find one at a shop that sells RV stuff. Why not try to use the one you have? It must have worked sometime and even now your main tank works off of it, I bet it's fine.

There should be some kind of ground wire running from the tank senders to the frame. Lets not worry about that for now and check the one wire that runs from each of the tanks. Is there any place along their runs that they can be disconnected? I assume you can't get to where they attach to the sending units.

[Jimbo]

I talked to a friend and he suggested that I use a test light on the switch. I did and could not get it to work. I tried it on the battery and it worked ok. When I tried it on the switch it would not even if I turned on the key. When I took off the two blue wires from the aux tanks the gage would not work for the main tank. This is driving me nuts. I might have to rewire the main tank through the wire system and then go from there. I am going to take the switch to a freind who has a volt meter and go from there. I have tried to feel around for the switch on top of the aux tanks I can only feel 1 wire coming off both of the tanks no ground wires Wish me luck on finding this problem. Jimbo

[Jimbo]

I think I got the switch figured out. I can not feel any ground wire coming off the aux tank. I can not figure out how to drop the tanks so I can get to the sending units, there is no straps going around the tanks. I can see where caeage bolts are gong down through the bed. I will try and get to it this week.

[68F250]

Ya know I would try something easier first. Stick a pin thru the sending unit wire coming off one of the tanks. Attach a jumper wire to the pin and ground it to the frame (must be a good ground connection). Turn the ignition key to ACC and flip the tank switch to one of the aux. positions. Watch and see if the fuel gauge moves up and past the full mark, it may take a few seconds. If nothing, flip the tank switch to the other aux. position and see if that works.

Then stick the pin in the other sending wire and try the whole scenario all over again. Whatever your results are should give some clues into which direction to look, hopefully not both!

[Jimbo]

If it goes past the full mark then it needs to be grounded from the sending unit? What if both sides do not go past the full mark?

[68F250]

If it goes past the full mark, then everything is working ok from the sending wire forward and the problem is in the tank.

If they don't go past the full mark, then there is a problem between the tank and the gauge that we'll have to tackle.

[Jimbo]

I tried the pin idea and it did go past the full mark. It worked on the right wires to the right tanks. I rewired the one tank so I could tell which wire went to which tank. So I guess I have to put gas in the tanks to see if they do work. If not then were do we go? I want to put some gages in do you have any ideas where would be a good place to put them. They are mechcanicl gages. Oil, Water, and Amp. You have been a great help so far on this porject. Jimbo

[68F250]

Super! So the fuel gauge, tank switch and wires to the tanks are all working properly. Put some gas in and let's find out! Not a lot, just in case you have to drop the suckers. How long have they been empty? There might be some crud and flakey crap inside. How did you know there was a problem if the tanks were empty?

Hey thanks a lot and I'm glad we're getting somewhere, was wondering if I was being helpful or just confusing. It's hard to troubleshoot wiring over the computer, especially when it's added in.

Go ahead and start a new thread on the mechanical gauges, we can all help you with ideas!

Barry

[Jimbo]

I put some gas in the left tank and it was not show anything on the gage. I think they have been empty for some time. I just got the truck about a month ago. It was setting at a freinds house for a while. He got it from someone else.

[68F250]

Hey sorry for the delay.

Bummer, I think you're gonna have to drop those tanks and check out the sending units along with cleaning out the tanks too. Safest way is to call around different radiator shops until you find one that can do it or set you up with someone who can. When removing the senders, try to preserve the gasket if it's not too bad. The senders could be stuck, broken or the float's bad.

[Jimbo]

Why a radiator shop to clean out the gas tanks? If I can not save the gasket where can I get them or the material to make one? How is the Leg doing? Thanks again

[68F250]

Calling radiator shops can be your quickest lead to finding out who can do it, either themselves or someone else who can. Unless you already know of someone, then go for it.

It's hard to say if you can find a gasket, don't know what it looks like. You could buy a sheet of gasket material that's similar and cut one out.

Thanks, the legs getting better each day and I'm beginning to walk without the cane. Good luck on your knee surgery this Friday, I'll be praying for ya. (Boy aren’t we a bunch of invalids.)