wiring is smoking on start up

[84cucv1ton]

Just finish up the work of my cousins truck. Everything is clean and tight the way it should be. While was a part we cleaned the grounds on back of the engine by the fuel filter..

All clean and tight. cranking the motor over to get the air out of the lines there was white smoke coming up by the fuel filter. Took it apart again all looks good. What am I missing? Thanks

 

[Warthog]

Refresh our memory. How long has it been since the truck has run?

Two things come to mind.

Some garbage on the GP resistor pack that heated and burnt

One of the fusible links on the 24v Positive Terminal Block.

 

[84cucv1ton]

3 4 months since its been run.. resister pack in gone.. 12v off the junction block above the relay.. i will check the fudable link... smoke was from the air cleaner and fuel filter housing....

 

[MakersTeleMark]

Could it be unburned fuel from trying to get it cranking, or is it electrical type smoke?

 

[84cucv1ton]

electrical type smoke and insulation melting.. warthog, do you mean the wiring in the plastic covering? i was thinking you meant the wire terminal. if so ones on the terminal look fine

 

[84cucv1ton]

just read it again.. you did mean the ones on the Terminal Block..

 

[84cucv1ton]

cousin said when he first got the truck he changed the fuel filter did the same thing its doing now.. cleaned the connections and it seemed to be fine.. now its back?? this is not making sense to me . missing some small thing

 

[84cucv1ton]

triple checked it again.. cleaned the electrical plugs.. still got the smoke.. the black wire over to the block and the small wire into the harness were cool to the touch the braided one was hot!!

 

[dstang97]

the braided one between the positive and negative block? or the ground strap?

 

[84cucv1ton]

ground strap from motor to firewall

 

[84cucv1ton]

anyone else ?

 

[doghead]

Replace it. It may be corroded and have high resistance.

Did you get fuel on it?

Starter may be drawing a high amp load(need rebuilding).

 

[84cucv1ton]

i think i did get fuel on it.. its pretty dirty.. starter seems to spin fine.. i will looking into checking the starter

 

[twomorestrokes]

Why don't you have someone else crank it over while you watch the area under the hood?

 

[Warthog]

triple checked it again.. cleaned the electrical plugs.. still got the smoke.. the black wire over to the block and the small wire into the harness were cool to the touch the braided one was hot!!

You have answered your own question.

The smoke is coming from the braided ground wire. One of you other ground wires is not making good contact and all the juice is flowing thru the braided wire. That wire is usually covered in oil/junk (fuel in your case) and it is getting very hot and burning off the junk.

You need to check all the ground wires going from the battery to the frame and engine.

My bet is the one from the 24v Negative terminal block to the engine is bad or loose.

Ground wires are VERY important for everything to work right.

 

[84cucv1ton]

thanks thanks for the help

 

[SSG ALBANESE]

I just installed a new additional ground strap. I went from the drivers side accesory sized bolt on the intake which goes into the head. Ran the cable under the brake booster to the lower bolt (cleaned) on the hood arm.

Cable used is about the same size as the actual battery cables, "thick". You cannot go wrong with a bigger ground. It actually fixed some electical issues for me. I would still replace the other one as mentioned.

Also I had some Fuse/links burn becuase my starter relay under the dash was bad. Is the starter acting weird at all?

 

[84cucv1ton]

that seems like a good idea.. little extra insurance.. starter is fine.. i have a the doghead relay mod....

 

[SSG ALBANESE]

Also you may want to take the trouble wire, cut it back one to two inches and just put a new connection on it.

Also just have someone turn the key to run and feel along the wires attached to the junction box to see if any of the wires are getting hot. I would do this on the GP relay as well, do a voltage test while you're at it. Trouble wires should get hot by just being in the ignition run selection.

 

[MarcusOReallyus]

This....

Ground wires are VERY important for everything to work right.

And this:

Cable used is about the same size as the actual battery cables, "thick". You cannot go wrong with a bigger ground.

Remember that wires can LOOK good but actually be corroded inside and have very high resistance. A voltmeter is your friend!