C2 Wire Harness Melt Down

[George C.]

I tried to start my car last night for the first time in four months. It was apart to rebuild the driveline from the clutch on back. The red wire in the engine harness fried, the one that goes from the starter to the horn relay to the alternater. I have chedked the wires on the starter, because I had that out. The wires were on right. The only electrical thing I did was to replace a missing backup light switch. I have no idea what would cause this so 1 am lost as to where to start looking for a problem. I need your help once again.

Thank you in advance,

George
#36908

[Ralph E.]

Re: C2 Wire Harness Melt Down

George,
Did you only replace the engine wire harness? If so, why didn't the fusable link prevent the short? I am about to change my engine wire harness this weekend. I hope you get explaination to this serious question. I will certainly be watching!

[Wayne W.]

Re: C2 Wire Harness Melt Down

There is no fusable link on a 67. If it didn`t get hot when the key was first turned on, I would suspect the starter.

[Ralph E.]

Re: C2 Wire Harness Melt Down

Wayne,
I know you are usually right with information. But are you sure in '67 the red wire didn't have a fusable link? I am not near my AIM & wiring diagram but I thought the wire to red wire starter to alternator to horn had a fusable link in line.
I know I shouldn't ask before looking things up but I'm anxious to find out.

Ralph

[Rick Miller]

Re: C2 Wire Harness Melt Down

The Chilton's engine compartment diagram I've got for the '67 doesn't seem to show a fusible link on the wire in question. FWIW.

[John H.]

Re: C2 Wire Harness Melt Down

67's have two fusible links in that (red main power feed) circuit - one (14-ga. brown) at the battery cable stud on the starter, and one (20-ga. orange) at the #2 terminal on the voltage regulator. There are two more (20-ga. orange) at the 16-ga. black/white wire at the horn relay and on the 16-ga. black wire at the battery cable stud on the starter solenoid, but they only protect the ammeter sense wires. Chilton books aren't a great source for accurate Corvette information.

The brown link at the solenoid on the red wire should have fried before the wire itself; dunno why it didn't.

[George C.]

Re: C2 Wire Harness Melt Down

Sorry I didn't include the year, mine is a 1965. Two more things I have noticed after unwrapping the harness. The wire from the heater motor which goes down to the starter motor has a female crimp on connecter which was is not attched to anything, also the grey two wire connecter on the alternator has a black wire and a blue wire, a new connecter has been spliced into the line, but the color coded wires are reversed. The alternator is not original, it is a 61 amp unit. There are no fusible links anywhere in the engine harness. I am still at a loss for what caused this, but intend to replace the red wire and hook everything back up to see if I get any heat before trying to engage the starter.
Thanks to all who are assisting.

George

[Bob R.]

Re: C2 Wire Harness Melt Down

I had a melt down which sounds similar to your problem with my 63. I went to start the car and the wires started melting. The wire from the starter to the coil melted. It turned out that the ignition coil was turned sideways the ground side of the coil was touching the shielding cover. It caused a short. You might want to check the shielding.

[Wayne W.]

Re: C2 Wire Harness Melt Down

Thanks, John. Some times these things run together and I forget. OldTimers I guess.

[Ralph E.]

Re: C2 Wire Harness Melt Down

I want to thank you guys as well. Looking at the '67 Wiring Diagrams John is correct. I have the harness in hand it it matches the diagram. Now all it will take is time to install.
George please keep us posted on what you discover is the problem.

[George C.]

Re: C2 Wire Harness Melt Down

I really hate to admit how stupid this one is. Somewhere along the line somebody put new battery cables on the car, and they are both blue. I managed to reverse the cables and put the hot lead to the ground and the negative to the starter motor. I replaced the red wire from the starter to the horn relay, the voltage regulator and the alternator. Everything seems to work, I cranked it over will start the car tomorrow and pray I didn't fry anything in the charging circuit. I think I have justified buyinh a new set of repro spring clip cables so I don't do that again. A new engine harness will also be ordered, but I can go for drive this weekend!!
I still don't know what the extra wire going from the heater motor to the starter motor are is for, but the assembly manual shows it and doesn't show it connected to anything?

Thank you all,

George

[Timothy B.]

Re: C2 Wire Harness Melt Down

George,

Can this extra wire to the starter be the ground for the wiper motor and heater blower? There is a ground that bolts with the negative battery cable at the starter.

[George C.]

Re: C2 Wire Harness Melt Down

Timothy,
That's a possiblity, since I do not have the original battery cables I don't know exactly what the configuration should be. It is a small, probably 18 gage wire with a factory installed spade lug on it. I will go back and check the manuals again.

Thanks,

George

[Rick Miller]

Re: C2 Wire Harness Melt Down

Agreed, Chilton's info is suspect, that's why I referenced the source and added 'fwiw.'

[John H.]

Re: C2 Wire Harness Melt Down

The "orphan" wire that's dangling (black with a large ring terminal on it) is the ground for the heater blower and wiper motor - it attches under the outboard starter attaching bolt, along with the negative battery cable.