Rookie needs electrical help/advice

[co-necked]

Hello everyone, I'm new to the board. I am looking for some electrical help. I have started to work on my Grandpa's old truck that's now mine. I put on a intake, new carb, dual exhaust, fuel pump, water pump, radiator, etc...(still looking for some headers though, any suggestions for a 3 on the tree would be greatly appreciated) Now I want to hear her and drive her, but the main wire from the harness going to the coil (+) keeps frying up. I don't know if the electric choke has anything to do with it. (was two connections on +, now 3) Don't know much, looking for help. Thanks

[GMCPaul]

The coil wire is a white cloth wrapped wire that is a resistance wire meaning it does not supply a full 12 volts, if memory serves me correctly it only supplies 10.7 volts, the carbs electric choke uses 12volts, run a seperate wire for choke from the fuse block spade terminal marked ignition fused for the choke.
GMCPaul

[JimKshortstep4x4]

GMC Paul has given a good answer and if you have a need, here is a link to the wiring diagrams for our trucks.

Jim


http://www.geocities.com/chevroletc1070/wiringdias.html

[co-necked]

Thanks guys. I really appreciate it. About to go check it out. thanks a mil'

[co-necked]

Now I re-routed the wire from the choke, but the main power wire, the white cloth wire keeps frying up. I'm really stumped. It seems like no power is getting to the distributor. Any more help would be great. Thanks

[dwaite72lnghrn]

It sounds like a short in the coil or a bad condenser.

edit: Did you pull the wires off the starter, or maybe pinch the wire from the starter in the intake or accessory mounting?

[co-necked]

I've changed out the coil. I think i did short it. But I connected a good one and the wire still fried up. It worked fine before i pulled out the engine and swapped the parts. I repainted the enginge compartment. Did i maybe mess up a ground?

[Brainchild]

Is the wire pinched between the block,and tranny or something like that?It is defenitly shorted out sounds like.

[dwaite72lnghrn]

When you say "fried up" is the wire burnt or sparks?
And are you replacing it everytime it does this?
Once a wire is "cooked" burnt blistered it needs to be replaced other wise the harness could have been damaged.
Take a light wire 26 gauge from the battery to the +side of the coil with heavy gloves on and NO other wires on the +side if the wire still burns you definately have a short in the coil.
Bad grounds can cause long term wires to overheat and fail but not melt like you are implying. Bad grounds normally cause weak spark, dim lights, intermittant problems and alternater over heating.
Basic check again, black wire from distrib goes to coil with a external condenser(possibly,maybe) on 1 side of the coil. High voltage in the middle. The other side of the coil should be the Yellow wire or white cloth wire.
I am not sure what year you have as the late 71-72 had a yellow wire and I think the early years had the white wire.

[Maximum Overdrive]

Not sure if its right but my understanding is that the resistence wire is a certain length to provide correct resistence, if it burned up it some and you shortened it then it no longer provides correct resistence. They do make a part that can be used to replace the resistence wire, cannot think of the name of it for the life of me though, and the part provides the resistence.

[GMC Jim]

Max OD...I think the part you are referring to that is used to drop the voltage to coil using standard wire is a ballast resistor. These are available from parts supply houses...