Electrical Joy

[Swerve-Driver]

1966 Chevy 283 3spd LWB HEI and corresponding alternator. Worked fine for ~6 years.

Earlier this summer I came into my garage to find that in the middle of the night, my truck crashed into my Camaro. Dang.
Examination revealed that for some reason the truck starter engaged in the middle of the night driving the truck into my car (spun the tire on the truck after it hit my car), then smoked the starter wiring harness, melting the small wires in half and stopping the signal to the starter. From what I can tell the truck was only driven by the starter. Engine did not start during this event. Thankfully, the damage was only to the vehicles. No crushed kids, no burnt garage, didn’t happen in a parking lot, etc….

Had the starter rebuilt, new battery and re-made the wiring harness (firewall to starter portion).
No blown fuses- before, during or after the accident.

The harness going to the starter has;
Wire that is always hot (Black)
Wire that is hot when the key is in the ‘run’ position (Red- formerly cloth covered resistor wire)
Wire that is hot when the key is in the ‘start’ position (Purple)
Wire for oil or temp sending unit. (Green)
I replaced the cloth covered resistor wire with standard stranded copper wire (Red).
I verified power to these wires with a trouble light.

When I turned the key to ‘Start’ position, the engine began turning over and attempted to start (hasn’t run since June) so I let the switch move to ‘Run’. The starter kept on going. Moved the key to ‘Off’ and it kept going. Jumped out and disconnected the battery. After re-checking everything, I tried again with same result.
Suspecting the key switch, I pulled it from the dash and removed it. I jumpered the ignition key harness connector and the engine began turning over and when I removed the jumper, the starter remained engaged and turning over. Had to disconnect the battery.

I tapped on the starter solenoid and the horn relay to see if that helped- no change.
I am out of ideas and not sure what to try next- any ideas?
Any input you guys might have is appreciated-
S-D

[tincan1966]

O would suspect the harness between the firewall connector and the ignition switch is also melted at some point.

[Swerve-Driver]

Thanks- will check that next (though I'm not looking forward to it).
S-D

[Metalaroundstone]

I would also suspect the solenoid.
Robert

[tincan1966]

Originally Posted by Metalaroundstone

I would also suspect the solenoid.
Robert

X2 ^^ I was "assuming" that having the starter rebuilt, it would include a new one, but that doesn't always prove to be correct.

[Swerve-Driver]

Thanks guys- I checked the wiring harness the best I could under the dash, bending it a bit back and forth from the passenger side firewall all the way back over to near the steering column. No change. If the starter checks out OK, I will have to do a more thorough check on the harness.

I am starting to wonder about the starter solenoid itself, even though it is new.

Although, at the end of the day, I still haven't answered the original question about what made the starter engage in the middle of the night and drive the truck into my car. So maybe I need to get the under dash harness out of there and really look at it. That doesn't strike me as a good time.

Thanks,
SD

[aerotruk63]

Is the cloth covered wire not a resistor wire? It's length is important as well. Sorry just read that you were aware of this fact. Are you running a stock coil?

[tincan1966]

You don't by chance have the Start and Run wires reversed at the starter, do you?

Altho with the HEI you shouldn't have the wire from the solenoid to the coil anymore.

If it continues to act in this manner,with the ignition switch removed from the harness I am suspecting either wired incorrectly or the solenoid is defective internally.

BYW the green wire at the firewall plug goes to the temp sender, should be a blue wire for the oil, unless you have OEM gauges, then it's hard lined directly.

[jtrichard]

since you have hei...take the "resistor" wire off of the solenoid(R terminal),try it and see what happens.....PS that wire is not a resistor wire,with org. coil it went to the coil side of the resistor OR resistor wire to give full voltage to coil for starting ...you may be getting voltage to the start wire somehow from that wire (the r terminal) if so it wont stop cranking

[Swerve-Driver]

TinCan- I had them switched once. When I turned the key to the 'run' position the starter engaged and wouldn't stop. So I switched them back- purple wire on 's' lug of the starter. The starter would engage when the key was moved to the 'start' position, but again the starter would still not turn off when the key moved to 'run' or 'off' positions.

JTRichard- I have removed the wire off the 'r' terminal of the starter- only the purple wire is attached to the 's' terminal. When I turn the key to the start position, the starter turns over and will not stop when the key is returned to the 'run' or 'off' positions.

I plan to remove the starter and 2x check the solenoid and its contacts just to rule that out before going much further.
Prior to removing the starter, I plan to short the hot lug and 's' lugs to engage the starter and see if the starter will stop turning when I remove the short. It almost seems as if the solenoid is sticking.

Thanks,
SD

[Swerve-Driver]

Aero- HEI contains the stock coil as far as I know (no MSD stand-alone coil or anything) . Have not tampered with the distributor since I bought the truck.
Thx-
SD

[1restorick]

1 had a 1978 Cutlass that used to just start cranking over, while I was in the house. If you disconnected the battery and reconnected it, it would stop. the starter had a broken part that allowed it to make an electrical connection at random. Weird but true!! Took awhile to find it.

[Swerve-Driver]

All in for the 'bad starter solenoid out of the box' team.
Disconnected all wires to starter except the large battery cable and jumpered the 's' lug to the battery lug- engaged and wouldn't disengage.

Time to pull the starter and see whats up in the solenoid.
Thanks-
SD

[tincan1966]

Originally Posted by Swerve-Driver

All in for the 'bad starter solenoid out of the box' team.
Disconnected all wires to starter except the large battery cable and jumpered the 's' lug to the battery lug- engaged and wouldn't disengage.

Time to pull the starter and see whats up in the solenoid.
Thanks-
SD

Glad you tracked it down!

Always remember when it comes to auto parts:
" new means new, it does not mean good"

[Swerve-Driver]

I removed the cap off the solenoid and found that when the 'washer' inside the solenoid would move, it would contact the wire coming out of the solenoid (wire to 's' terminal) and would cause the starter to keep cranking until I disconnected the battery.
Bent out of the way so it clears and truck finally starts and runs again.

Now to re-hang the repaired fender.

What an episode.

Thanks for the insights-
SD

[Irishbleueyes]

Originally Posted by Swerve-Driver

I removed the cap off the solenoid and found that when the 'washer' inside the solenoid would move, it would contact the wire coming out of the solenoid (wire to 's' terminal) and would cause the starter to keep cranking until I disconnected the battery.
Bent out of the way so it clears and truck finally starts and runs again.

Now to re-hang the repaired fender.

What an episode.

Thanks for the insights-
SD

So, what'd we learn? Not to do it again, whatever it was we did... LOL

[jmack91z28]

Wow that's scary, so that washer caused a connection in the starter circuit over night?

I bet you'll keep the truck in neutral for now on in the garage won't you?

[tincan1966]

As cheap as solenoids are, I would have bought another one!