Bad electrical problem

[Richard M.]

Re: Bad electrical problem

Yes......And with 2 fusible links, if there is a short circuit downstream on the loads of the heavier gauge total current capacity, the links may not do their job and protect those downstream circuits. It's possible wiring downstream could then overheat and cause a problem.

Since you have a marginal and unpredictable connection on the stock bulkhead connection, just remove it and with the new wiring and FL you'll have a factory like electrical connection.

Your other option is to repair both twinlock connectors in both the engine harness plug AND the fuse panel bulkhead connector. There is ample wire in both places to replace with new. Once repaired you should have no problem for a very long time.

Rich

[William F.]

Re: Bad electrical problem

Richard,
Maybe I missed reply, but would still like to know why it's a bad idea to have parallel wires if you're going to add a jumper wire to horn relay terminal.
Thanks

[Richard M.]

Re: Bad electrical problem

Walter, see post #46. I replied to Dan's(#45) and to you.

The reason you may not have seen my reply is that you're probably viewing using Hybrid Mode. In the gray bar near the top of this page click on "Display" then a drop down appears. Click on Linear mode and the top of page of all of the posts in a thread will be seen with the most recent up top. Scroll down for Linear order with the first post at the bottom.

Hybrid mode can confuse users as it doesn't order the posts chronologically. If someone replies to let's say the 14th post and quotes that poster, the new post shows up there, in the middle of the thread,and not at the bottom of the page. This happens in in Hybrid mode.

With Linear mode, the last post will always be up top, whether it's replying to the last post or one in the middle......IIRC.

Rich
ps this post should now be #47

[Noel B.]

Re: Bad electrical problem

Richard - Hi, this is Noel (the guy who started this thread). Thanks for all of your input. As stated previously, I added a #12 red wire from the horn relay to the "bat" terminal on the fuse panel. I installed a 30 amp fuse at the horn relay for protection. Seems to be working so far.

I decided that I didn't want to tear into the bulkhead connectors since jobs like that tend to cascade into extra work to fix things that happen when old stuff is taken apart. So I went for the bypass wire. So far I haven't removed the old connection to the bulkhead connector but I may now that I have heard your reasoning. I was thinking that if the bulkhead connection had some resistance most of the current would go through the new wire but I see your point.

Thanks again.

[William F.]

Re: Bad electrical problem

Richard,
Do I have to take the cabin fuse panel apart to get to back side of it to "connect new 12 red wire with spade terminal to power window terminal?"

[Noel B.]

Re: Bad electrical problem

My car is a 66 so it might be different but I didn't have to take anything apart. I connected to a spare lug on the fuse panel labeled "power". It is located next to the fuse labeled "windows". Very simple.

For protection I installed a 30 amp fuse at the horn relay. I may disconnect the old wire going to the bulkhead connector per Richard's suggestion.

[Richard M.]

Re: Bad electrical problem

Richard - Hi, this is Noel (the guy who started this thread). Thanks for all of your input. As stated previously, I added a #12 red wire from the horn relay to the "bat" terminal on the fuse panel. I installed a 30 amp fuse at the horn relay for protection. Seems to be working so far.

I decided that I didn't want to tear into the bulkhead connectors since jobs like that tend to cascade into extra work to fix things that happen when old stuff is taken apart. So I went for the bypass wire. So far I haven't removed the old connection to the bulkhead connector but I may now that I have heard your reasoning. I was thinking that if the bulkhead connection had some resistance most of the current would go through the new wire but I see your point.
Thanks again.

Noel, Yes I certainly remember you were the thread starter and your issue. You, Walter, and many many others have had that identical problem. When a car dies with no warning like that it's nerve wracking. Very bad and could be dangerous in some situations. In fact, I myself had that problem about 9 years ago with my wife's '63 300hp Powerglide coupe. However, when the car died I didn't know what it was. Quick funny story....well at the time, not so funny.

Shortly after we got the car in Dec 2007, a nice driver with only 67,000 original title documented miles, I was driving it to a shop get new tires and alignment. Heading down busy Rte 1 near Vero Beach Florida there was some construction and 2 lanes went to 1 lane with barricade barrels to the right. There just happened to be a Indian River Sheriff's Dept car behind me in slow-down traffic. We were all then stopped. I'm sitting there idling, then poof, engine stopped. I looked at the clock, dead. Tried a few other items....nothing.

I popped the hood release and got out and lifted it up. Just then the cop saw it was dead and turned his blue lights on and moved a few barrels and was directing cars around me to keep traffic moving. I was nervous and embarrassed and angry. After the cop got traffic going around me, he walked up and started talking Corvettes and how nice it was. I chuckled and I recall I said something like..."Yea, when it runs...!!".

So after a few more words, I started looking at wiring etc. I suspected that the bulkhead Red-Wire-Syndrome got me. I reached down, wiggled the bulkhead connectors, went back inside.......and it started right up! "YES"....... I was sooooo happy!!......I think a little pee came out.

The cop looked at me and said......"WOW, YOU'RE pretty good!" I thanked him for being there to help and redirect the upcoming 50 mph stream of cars approaching. Then I got in and drove off to the shop. I didn't touch the connectors and panel until I got home. I spent much time checking then pulling the fuse panel when I saw the green corrosion on the #12G Red wire pins. I cleaned and re-bent the Twinlock #12 Reg pins on the harness and then the bulkhead panel. In the process, the pin on the panel Red wire broke in half. I managed to replace it with new and a good soldered connection. Was fine ever since.

It's good practice to get in there and check and clean those pins as part of a preventative maintenance program.

Richard,
Do I have to take the cabin fuse panel apart to get to back side of it to "connect new 12 red wire with spade terminal to power window terminal?"

William, Like Noel's '66, nothing on the panel needs to come apart to add the Red wire with Female spade terminal. Those 2 side-by-side blade Male terminals at the lower right can be accessed easily. Here's a '67 panel, just like yours. Also a shot of the backside. You can see the #12G Red wire from the harness to the 2 lower left fuse feed(as viewed from front), and the #12G Red wire going over to those 2 male blade terminals. Those 2 #12G Red wires are spliced together in the harness as described in the post with the Wiring Diagram photos.

Rich



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[William F.]

Re: Bad electrical problem

Rich,
You say plug my new wire into one(either one?) of the 2 slots on the lower right of the fuse panel as looked at from the front? Are these the "power window connections"? What ordinarily goes in those spaces? My car does have power windows, does that make a difference in how I should make connection??

[William F.]

Re: Bad electrical problem

Rich,
I went and looked at my fuse panel. A wire is plugged into the left plug of the 2 "power window plugs" in lower right side of panel since my car has power windows. Is it ok to connect new red wire to the vacant right side plug? "batt" is printed to the side of this vacant plug.Think this will be my last(I know you hope) question on subject.
Thanks!

[Richard M.]

Re: Bad electrical problem

Rich,
I went and looked at my fuse panel. A wire is plugged into the left plug of the 2 "power window plugs" in lower right side of panel since my car has power windows. Is it ok to connect new red wire to the vacant right side plug? "batt" is printed to the side of this vacant plug.Think this will be my last(I know you hope) question on subject.
Thanks!

William, Yes those 2 side-by-side terminals are tied together so you can just plug it into the one that's free.

edit.....I made a mistake about the Buzzer earlier and corrected it below....

If you has Speed Minder Speedometer, the Orange Buzzer feed wire(#12G IIRC) connects to the other PW/Bat fuse panel terminal, but there is a tie connector port on it that can be tapped into for other loads. The Orange power wire for the buzzer ties to the other fuse panel terminal so both are then used.

Here are photos of the Buzzer wiring. Red is PW, Orange is the Buzzer feed.

So one more thought, for both you and Noel. It may be wise to use the same plastic connector and female terminals for the "new" replacement wire as shown in the photos below. The plastic connectors will help guarantee safety and have a nice solid feel when installed. If you guys can't get them locally, PM me both of your addresses and I'll drop you each a plastic connector and a few new terminals in the mail.

Rich

[Richard M.]

Re: Bad electrical problem

Edited previous post...

[Richard M.]

Re: Bad electrical problem

So....the more I think about you gents adding a new #12G Red wire feed, I now have another suggestion.....

Remove the engine harness #12G Red wire from the harness plug that plugs on to the fuse panel bulkhead connector there in the engine bay. This will then deem that old removed wire form the Horn Relay Buss Bar totally open on both ends. Later I show how to do that.

Below are a group of photos I just took of a old '66 harness that I replaced not that long ago. It was totally covered with plastic spiral tubing. It was pretty bad, AND dangerous. In a earlier post I mentioned I found some bad internal wiring on it and I'd shoot some photos when I got a chance. The black wire going to the Battery Gauge was melted stuck to the Solenoid Purple wire. It had exposed strands showing. IF....the Gauge wire(always hot) had eventually burned and melted into and connected to that Purple wire, the car would start by itself. Very bad. Also, the main Feed #12 Red wire was also compromised with insulation missing and green corrosion on the wire. This harness was a accident waiting to happen. BTW, the car got a brand new harness. If your harness looks like this, disconnect your battery right away and get a new harness.






















So he're a sequence to remove that Red wire from the connector. You can get the special tool to release both Twinlock pin sides at once, but I actually like this method better. I made a simple pin removal tool from a large paper clip by hitting the end of it on my vice with a hammer. Do one side at a time and pull the wire out the back. You'll have to unwrap the harness tape a bit to access the pin. After removal simply tape it back up and tuck it away, then rewrap the harness to the plastic connector block.

To reinsert the pin, pry up slightly on the small tab on each side then re-install into the housing. Note the pin can only go in one way for it to properly lock as it has a locator pin on the side. Also note the result of overheating that Red wire as the plastic has melted.

Rich



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[Noel B.]

Re: Bad electrical problem

Richard,

Thanks again for all of your detailed help. I'll have to wait until after the holidays but then I will take time to inspect the wiring harnesses per your suggestions. This electrical issue was tough for me to isolate since it was very intermittent - I could go for 5-6 months without trouble. Then when it happened it would fix itself before I could do any checking. Finally when the clock stopped and everything shut down on my street I literally ran to my garage to get the wiring diagram and my meter. Luckily the power stayed off long enough for me to check voltages at various points and target the bulkhead connector. Then I banged on the connectors and the clock started up so I knew where the problem was for sure.

As you pointed out this is a scary problem since basically all of the power is dead. I shudder to think of the times I drove back from Sacramento on Interstate 80 (five lanes wide) at night before this issue ever happened. It would have been so dangerous to have my engine stop and lights go out at 65 mph in the middle of the freeway. So I am glad that I have located the issue and am at least safe for now. Luckily, when the issue happened I was generally in town and could push the car to the side - very frustrating though...

As a further note, I have had the Vette for three years now. It was built the year I got my drivers license in 1966. I was in high school and I thought the Stingray Vettes were the coolest cars ever. However, it took me about 50 years to finally buy one (life was busy and we had to put two kids through college, etc). So it's pretty exciting to be able to cruise around now in my dream car.

Again thanks for your guidance,

Noel
Sonoma CA

[Joe T.]

Re: Bad electrical problem

Wow! Very interesting post. I have a 66 427 BB. When I try to open headlight doors all power goes out. I can wiggle the firewall connector and power comes back on. This only happens when opening headlight doors. Not when closing. It's a new switch. Although I had the dash out to repair the tachometer and may have moved or shorted out the headlight door switch. What is confusing is wiggling the main connector on the firewall to recover power. I have read about C2 red wire syndrome.