Another Mystery Wire

[Chief Brody]

I was under the truck today thinking about dropping the transmission pan when I saw this bare wire hanging down behind the pumpkin.

It is so dirty I can't really make out the color, but after some brake cleaner it appears green...
It runs up into a sleeve and that bundle appears to have wires coming from the starter and running up to or behind the alternator.

Anybody know what this wire is?

Also, when I was cleaning it, I was tugging on it and when I pulled down on it the bundle would spark...one of the wires was shorting out on something...
looks like I need to replace this...whatever it is....

 

[4X4HIGH]

The only green wire I can think of is for the water temp sender.

 

[Chief Brody]

The only green wire I can think of is for the water temp sender.

maybe it's not really green...would the water temp sender wire be in that trunk? I currently have my temp sensor hooked up to a wire that comes out of the trunk on the firewall and runs very close to the carburetor...

 

[K85 Octane]

I remember the AC compressor having some green wire.
what was sparking? The green wire or something else? And was the ign on? hmmm

 

[Chief Brody]

I got some pictures coming...no not the a/c...it does have a green wire.

 

[Jessie James]

Can you snap a photo of where this is and let us know what year your truck is?

 

[JDNobodi]

I was under the truck today thinking about dropping the transmission pan when I saw this bare wire hanging down behind the pumpkin.

It is so dirty I can't really make out the color, but after some brake cleaner it appears green...
It runs up into a sleeve and that bundle appears to have wires coming from the starter and running up to or behind the alternator.

Anybody know what this wire is?

Also, when I was cleaning it, I was tugging on it and when I pulled down on it the bundle would spark...one of the wires was shorting out on something...
looks like I need to replace this...whatever it is....

The pumpkin? by the rear axle? or the front? There should be a green wire in the "ribbon strip" going to the back for the rear right stop/turn light. It should only have power when the brakes or turn light is on. But that is on the other side of the engine. What year is your blazer? I'm thinking if it is a 73, it should have came with points. I know on my old 73, I had an extra wire that came down from the coil to the "I" (I think) post on the solenoid. I took the wire out when I converted to HEI in the early 90's. I can't remember the color of the wire though.

Edit-I found a diagram, and the wire the goes between the solenoid and coil should have been yellow.

 

[K85 Octane]

 

[Chief Brody]

The wire is out of focus but you can kind of see it here, and in one of the pics you can barely see the wire but if you look for the wire you can see it...sorry the autofocus focused on everything but the wire:

 

[Chief Brody]

front pumpkin, 1974 K5

 

[JDNobodi]

Does your fuel gauge work?

 

[Chief Brody]

Does your fuel gauge work?

yeah...it's wire is in a ribbon that runs down the drivers side frame rail

 

[Chief Brody]

Not to confuse thing more, but here are the wires I have running to my water temp sensor...it is black...I have no idea what the brown wire is for:

 

[Chief Brody]

I went out to try to get a better picture, and wouldn't you know it...the camera battery went dead...got these...but not much better:

 

[4X4HIGH]

Just to let you know, that water temp sender is not in the factory location and DOES NOT have the correct color wire going to it either. Factory GM water temp senders were always in the left cylinder head and had a green wire connected to it.

 

[K5_Fla]

+ 1

 

[Chief Brody]

Just to let you know, that water temp sender is not in the factory location and DOES NOT have the correct color wire going to it either. Factory GM water temp senders were always in the left cylinder head and had a green wire connected to it.

That could explain some things....those black and brown wires...what do you think they are? Automatic choke?

The PO had installed an aftermarket under the dash temp gauge, but he installed it on the passenger side of the block. That green wire I have dangling would be in that area...I bet that's what it is...I need to get a temp sensor put in there and hook that wire to it and see what happens...the drivers side of the block has a plug in it and doesn't appear to have ever been removed..it's painted the same color as the block..

I am still concerned about the shorting arc...

I think these pictures show that same bundle on the top side...where the red wire is:

 

[4X4HIGH]

Someone has definately been in there doing something for sure as i've NEVER seen any wire loom anywhere near the fuel pump area ever.

 

[BoondocK5]

On the left side down where that is, could it be one of the wires to the back up lights, via the reverse switch on the trans?

 

[JDNobodi]

yeah...it's wire is in a ribbon that runs down the drivers side frame rail

That is not factory in a 70 square body blazer and pickups. The wire for the fuel gauge should leave harness by the starter and run down the passenger side frame rail. It should be the ONLY wire that runs down the passenger side frame rail.