electrical help

[Youey]

back in early January had a small electrical problem, left me stranded with no headlights only could hot wire the truck so i could get it off the road and wait for a tow truck to show up. im pretty sure it this is in result of some led headlights that i installed, possibly from the led fans drawing too much power. so i replaced everything that was burnt up fuses, headlight high switch, headlight switch, and the starter but that wasn't in result of the electrical. everything seemed to be going ok after that. the trouble im having right now is everytime i go to turn the key to start the truck i get a fizzle/click coming from the starter solenoid. I replaced both battery cables with larger ones thinking that whatever happened caused maybe the cables to burn up on the inside. that didnt solve the issue. ive jumped out from the harness in engine compartment the purple wire still get same effect. my only guesses is right now is it possible the HEI coil is somehow shorting it out or affecting it not to crank? funny thing is i thought it was the cables because i moved the one going to the starter and truck started perfectly. so confused about what could be the issue, its not like theres a ton of wiring here. my only other guess if that has nothing to do with it, the purple wiring from the accessory going to the starter has some sort of damage to it. which i have not seen and the wiring itself is only about 6 years old. hopefully someone has a clue where for me to look next, thanks for the help! if it helps its a 69 stepside.

[my67c20]

You are right, that there is not much wiring to these trucks. It sounds like you have an HEI, but what else has been changed from stock? I would get a hand on a wiring schematic (search the board). Disconnect the engine bay harness from the firewall, the battery and other circuits, grab a meter and start checking continuity to make sure you do not have a burnt or shorted wire buried in a harness. Be sure to pull on all terminals, lugs etc to make sure they are not loose. Repair and clean everything, including any engine or frame grounds. Then plug in the harness to the firewall and only those things required to fire the truck up. Keep in mind the coil needs juice and the starter to fire it up. Don't drive it around like that since you will be pulling juice from the battery. If that works, you know as a basic engine it runs. Then one at a time add the circuits back into play. Pretty sure that by taking your time in a systematic approach the problem will show up really quick.

[Youey]

Ok so a wiring is completely stock except the hei and I do have vintage air which had its own wiring. I can go over all the grounds again. I have the 2 prints of the electrical diagrams. Laying a screw driver over the starter I get the same effect if that helps any. Only thing I haven’t done yet is check the circuits with continuity, only jumped out from the harness to bypass the ignition switch. What wiring would you start with purple ignition?

[Youey]

Can an hei cool short out causing starter to get not to crank ?

[my67c20]

Unplug the connector from the distributor and see. If you tried to manually jump the starter and no luck, then yank the starter and take it to autozone or others and have it checked out.

[Youey]

Originally Posted by my67c20

Unplug the connector from the distributor and see. If you tried to manually jump the starter and no luck, then yank the starter and take it to autozone or others and have it checked out.

Starters brand new ac Delco, this problem existed before I changed this.

[Youey]

Pink wire from distributor is fine. Didn’t see any isssues there and I took off the cap to inspect coil looked ok.

[my67c20]

Is the battery any good? Is the battery fully charged? There is nothing in the starting circuit except battery power to starter & ignition switch to starter. If you eliminate the ignition switch, and the connector to the distributor is disconnected, the thing will crank, but not fire. Do you still have the voltage regulator, or have you switched to a newer alternator? Just tossing thoughts out there, since I am not there.

[Youey]

Ah did forget to mention I do have the newer Alternator. I’m gonna try and just disconnect dist and see if it cranks. Battery has full charge.

[Dead Parrot]

Make sure the battery posts are clean. They can look clean and be mostly non-conductive. Same for cable ends. Give everything a good going over with wire brushes.

Wiggling a cable and it starting is a clue. Also check any cable near or touching the cable you wiggled. Possible that cable moved the one that has a bad connection.

[my67c20]

Anything new to report on what you tried, etc?

[franken]

The HEI won't cause the starter issue. Also forget the headlight wiring.
The ignition switch through the NSS turns on the solenoid, which in turn switches on the starter. If there isn't enough current to engage the solenoid, it won't switch on the starter. Measure the voltage to ground at the solenoid S-terminal with the key in the start position.
Saying the battery is charged is meaningless w/o a voltage measurement to the nearest tenth, ideally with a bit of a load.