melting power wire.

[Joseph R.]

Re: melting power wire.

thanks for everything Rich. if we meet at corvettes carslile or aaca in Hershey I will buy you lunch. that is the least I can do for all your help. My brother mike (63 coupe- top flight) is coming to stay with me in July we are going to a model t tour with his 15 t. I hope he can straighten me out.
Joe

[Guest]

Re: melting power wire.

67 relay should be the same as 66 there a ground wire on the right side of relay, it grounds the relay to get a proper ground the above diagram show a solid ground on that connector , remember it's hard to find a good ground on a fiberglass body, maybe the relay is a aftermarket and there wired different , my 67 has the original harness and horn relay on it

[Joseph R.]

Re: melting power wire.

hi everyone that has been so great. well here is where I am at.
battery hookup pos and neg no smoke no circuit breaker with power probe
headlights turn on
headlight motors don't work
horn works
turn signal left and right front and rear work
backup lights on all the time that light switch id pulled out
light notification flashes red
turn signal indicator works
windshield wiper. I can hear washer click but arms do not move when on
radio works
clock works
I have bought a 30amp inline fuse and so when I have someone with me I willl hook up inline fuse and try to turn over motor.
it looks like I am slowly getting there
heater blower does not work
r 12 air con not charged so I haven't tried to turn compressor on. there is air co oil in system - restored by classic air Tampa fl
brakes no leak,antifreeze no leak, power steering major leak at pump

[Guest]

Re: melting power wire.

i would replace the complete engine wire harness, looks like the short caused alots of damage within the harness

[Richard G.]

Re: melting power wire.

One can just borrow the 40A circuit breaker located on the lower left hand side of the dash just inches in front of the fuse panel.
Just remove it and tape up the wires at that location and rewire it into in the battery + circuit.
Test your new or used harness this way.

This circuit breaker is a good place to confirm power to your headlight motor circuit as this is the breaker for the motor circuit.
I'm glad your radio didn't get damaged.
My grandson helped my wife jump her Highlander. He crossed the jumper cables.
Took out the master fuse and the radio in a nanosecond.
Rick

[Joseph R.]

Re: melting power wire.

I bought this from auto zone I have 25 amp fuse in it but I have 30 amp fuse. it is rated 30 amps and I just added the clips thought I would attach between battery and main positive line

[Richard M.]

Re: melting power wire.

I bought this from auto zone I have 25 amp fuse in it but I have 30 amp fuse. it is rated 30 amps and I just added the clips thought I would attach between battery and main positive line

Joe, NOT Battery cable. It will blow the fuse when you crank the starter. The fuse should go between battery and Red feed terminal(removed) at the solenoid.

[Joseph R.]

Re: melting power wire.

ok and thanks

[Joseph R.]

Re: melting power wire.

here it is ready too go. I did wrap with electrical tape so it wouldn't short at the exhaust t

[Joseph R.]

Re: melting power wire.

ok here is the latest. used 30 amp fuse and engine turns over so I hooked battery up and solenoid it still works. no short detected.
so here is what works and doesn't
working: main lights, running lights, turn signals front and rear, power windows, radio, clock, horn, backup lights, windshield washer, engine turnover ( have not added gasoline yet ).
not working: headlight motors, instrument cluster lights, heater blower
all fluids are in and no leaks.
once I get these last electrical components working will have to adjust transmission linkage a bit and then add gas and start her up.
any thoughts appreciated. another ncrs Pittsburgh club member has volunteer to come over but I want as much fixed to not waste his time. again so much thanks to everyone

[Richard G.]

Re: melting power wire.

Start at the beginning;
Check for power at both sides of each and every fuse.
Use one of the test lights with the bulb in the handle.
Ground one end and check for power at each end of every fuse.
I have had defective fuses out of the box. Issue can be hidden by the cap at the end.
Others will have more detailed checks and inspections.
We can go from there.
Rick

[Joseph R.]

Re: melting power wire.

good morning gentlemen,
As you can see from the thread I have had problems with the wiring in my 66 air coupe 427 - 390 hp. I have everything working now including starting and running except for one thing and I was hoping that someone has this answer. My heater air con blower is not working. I have a red wire that is not hooked up. It is labeled a horn relay wire on the dr rebuild wiring chart but the connection is too large and it can't possibly reach the horn relay. I believe it is to go on the power connection of the solenoid because it will reach and it is the same color and number ( red 14 ) as the red already hooked up and that wire( along with a concomitant black/white wire goes to the horn relay. I tried to charge the wire through my power probe but no action. The thirty amp in line fuse is intact. thanks in advance

[Michael A.]

57045FCE-2BE8-4F2E-981F-5A6BCD64164C.jpg

Once again, I have to thank you for your posts Richard. They are a great resource.

Cheers,

Joe I did a search of your Power Probe III and now see the specs.

https://static1.squarespace.com/static/582b77aa6a4963c3f199b0a5/t/586e87f92994ca37b452c432/1483638778185/PP3_English-PDF.pdf

There is no way it will supply enough current for the starter solenoid. That is why the 8 AMP circuit breaker opened when you tried to crank. See page 13. IIRC a solenoid needs around 15-20 amps.

All of your other tests tells me your wiring appears properly connected. However, you may be missing the Black ground to the wiper motor if you hear clicking and no arm movement. Check that the Black wire Plastic housed spade terminal is connected to the wiper motor terminal lug.

One other potential issue..... Your photo shows 2 Black grounds to the starter mount bolt. There should only be one, for the heater fan & wiper motor ground just mentioned. You may have the 18G Black wire for the BATTERY meter there. Your BATTERY gauge will peg in one direction if wired that way. It won't cause a Power to ground short, just a miswire to the meter Source terminal. That Black(18G) wire should go to BAT+ on the solenoid. It is the Source wire for the meter. The Sense wire is the Blk/Wht at the meter, which comes from the Horn Relay Buss bar.

Panel fuses are not involved in the Starter or Ignition circuit. I can't see the wiring colors in your other photo.

Rich

[Richard M.]

Re: melting power wire.

Mike, Sorry to hear you lost a harness due to the Wiring Diagram error. I'm glad you found this in time.

Answers to your questions below... Rich

I feel that the only thing damaged was the harness because it was a direct Power to Ground short between the Red(12V from battery)/Black(Ground from battery) wires at the relay buss bar. Both wires took full battery current and since the resistive path is 0 ohms it couldn't handle the load. The high current path was direct, not through any other components such as the alternator. An example of alternator diode damage would be if the Positive and Negative battery cables were reversed. Those device are polarity sensitive.
This is a good plan and one I always adhere to. You can test just about everything except the start/crank function. If all tests pass then chances are if the Ign switch, Purple wiring path, and starter solenoid and starter motor are good, it'll work.

3) What do think that second terminal, next to the BAT terminal on the Horn Relay, is actually for? Just curious.

It is simply a secondary terminal attach point designed into the relay. It may also be used for the optional C60 A/C wiring IIRC. Some other car or trucks models may use that extra lug for other options as well.

4) You mention an issue with the 2 grounds attached to the starter mount. My AIM shows 2 wires grounded to the starter motor mount. Those two wires are the Brown line coming directly from the BAT- terminal and the other line is 14B in the harness which is coming directly from the heater motor. Apparently the W/S wiper motor is grounded through the heater motor to the starting motor through his line. (Photo attached). Is this another error in the wiring diagram? If yes, where should the 14B wire from the heater motor be grounded to?

No not a error. Yes the Heater motor and Wiper motors use a unique 14 Gauge Black ground wire wire comes from the starter mount bolt, along with the Brown Battery cable under the same bolt. The Black ground wire path originates at the mount bolt, then a terminal to the Heater motor. Attached to that same terminal is another Black wire which terminates at the Wiper Motor for its ground.

[Michael A.]