Need help troubleshooting electrical (waggy turns over, no start)

[Blake]

I've spent the past couple of hours searching and reading posts on here.

I drove the waggy home today after work. It was running GREAT. Got home where my neighbor needed me to pull his truck out from the side of his house. Waggy pulled the truck fine and was running PERFECT.

Parked and killed the waggy. Came back an hour later to move it to my drive way. Now it won't start.

Here are my symptons and what I know- please help with troubleshooting.

'83 Waggy with Chevy TBI, MSD 6A, TFI Ignition

• Engine cranks good - no start
• All fuses on the fuse block are good
• Battery is fully charged
• All grounding is tight
• All electrical function- interior lights work, radio works, cig lighter works, headlights work, brake lights work, turn signals work.
• TBI computer is not receiving power - thus no fuel pump
• blue wire (battery side) of starter solenoid has 12V when key is on.
• Red wire (starter side) of starter solenoid has .35 volts when the key is ON. (zero voltage when key is off)
• Same red wire (starter side of starter solenoid) has MELTED wiring from the solenoid on into where it merges into the main engine harness. It does not appear to have melted other wires and moves freely within the harness.
• Large (10 or 12 Gauge) Yellow wire comming from the ammeter to ?? get's HOT when you leave the key on for a few minutes. ( I don't know if this is a problem or would be normal if you leave the key on without the engine running)

So basically my problem (I beleive) is that my computer is not receiving power (from the starter side of the solenoid) and the MSD is not receiving a spark signal from the comptuer.

The starter solenoid itself is only a few months old. I "rewired" the underhood of the waggy about a month ago. Have since driven 400 + miles with no issues.


My questions are:

Should the starter side of the solenoid (red wire) have 12V power when the key is "on"? I'm really sure it should as this is where my TBI get's it's power and has been working for well over a year.

What would cause the red starter solenoid wire to get so hot that it melted the insulation.

To my knowledge, it still has the orginal ingition switch. If that was having a problem, it wouldn't crank over right?

Thoughts?

[yankeedog]

fusible link?

[jeepfan93]

If I'm reading that correctly, it's early and not even one cup of coffee in me yet, you said 12 volts on the starter side side of solenoid? That would energize the starter.You have a dead short someplace, that would make the wire melt. UNless someone here can reach through the computer and look at it you need to go digging around. You could have a bad ammeter. Get rid of it and put in a voltmeter to start. Obviously with things being melted you willnot have power to your ECM or MSD box. Reverify everything you "rewired" and run new wires that are melted. I did the creative wiring on my 91 last year with a couple of terminal strip for a boat and have been happy. My biggest problem was shorting the battery lead going to my starter relay on the case of the realy itself. Good luck and happy hunting.

[Blake]

Update - the waggy starts now.

I put in new wire to replace the melted wire and I bypassed my kill switch. In addition, I put in two in-line fuses. One in between the 12V + key switch and the MSD and one in between the 12V + key switch and the computer.

The fuses *should* burn up before the wire melts right? They are 25 amp fuses.

Funny thing is this - Ever since my 401 / TBI / MSD swap I had to have a manual kill switch to kill the motor. Now the motor dies right away (when I turn the key of).

Another question - (I think this is related to the kill switch mentioned above) I have a small, solid core brown wire that is in line with the 12V + key switch wire. I"m pretty sure this wire goes to the alternator. I'm also pretty sure that this wire was "feeding" the MSD, causing the engine to not die when turned of.

What is the small brown wire?

[jeepfan93]

Small brown wire is the resistor wire, it knocks down the voltage going to the stock ignition module. Generally speaking when working with the MSD most people, myself included, need to put a diode inline with the ignition wire going to the MSD to have it shut off with the key because of electrical bleeding.
Those 25 amp fuses will do the job for you and prevent anymore burnups. Mine is wired through a relay and a fuse for abttery power, stock ignition keyed source, then directly to the coil. Runs like a champ. Good find hope she stays together now.

[yankeedog]

ALWAYS ALWAYS put the fuse as close as possible to the battery,this way the wire doesnt burn up to save the fuse.