MF64VETTE

I have lost power in my 64 vert twice in the past two days. Once while putting down the headlight lamps with the ignition switch to on, motor off. Had to get a jump. Had battery checked, it was OK. The 37 amp alternator was putting out 32 to 35 amp. Drove car, no problem. Got home from work last night, no courtesy lights, no radio, nothing when I turned the ignition switched. I had a new ignition harness and bulkhead connector installed last summer after the original one on the car crapped out. For the heck of it, I unplugged the bulkhead connector at the firewall and plugged it back in and voila, the courtesy lights came on and the car started. Any clue as to what is going on? I didn't see any corrosion. Could the connector have come a little loose? Or do I have a bigger problem?

Chuck Gongloff

Unplug it again and put some dielectric grease in the fittings. See if that helps.

If you put a new "under the hood" harness in, it still plugs into the "old" harness connected to the fusebox, etc. Chuck

MF64VETTE

Chuck:
I'm a newbie at this electric stuff. What is dielectric grease, where can I buy it and how does it help the connection?
Thanks

wombvette

OH NO, You have air-car-itis. Interesting that it is doing this with a new harness, but why mess around. FIX IT RIGHT. Unplug the connector. Look for the main red power wire in the corner of the plug. Remove both plug fittings and run a good power wire through the hole. Solder on both ends and rap the harness in tape. You litterally cant tell it has been done, and you never have to worry with it again.

Hitch

Wayne I didn't even register that even NEW harness' might have the same problem as the old fuse block to engine bay harness has.... Hmm.. Just for others info I had a similar problem where I was working in the drivers footwell replacing the rear harness and afterwards I had no power... Long short of it I had bumped the fuse block and it dislodged the engine bay connector thus I had no power at the key,no courtesy lights,no headlight motor power and no brake lights... Now I know these are all things that are fed hot no matter if the key is on or not... If the main power at the fuse block is not connected to the engine bay connector you will find you will have the above problems... Just thought I'd let you guys learn from my two days of troubleshooting...Dave....

Chuck Gongloff

Dielectric grease can be bought at Radio Shack, etc. It's a silicone based lubricant that supposedly improves electrical conductivity and prevents corrosion within electrical connectors. I use it all over my cars.

As Wombvette says, check the "red wire" too. Chuck

magicv8

The term dielectric implies an insulator and is the opposite of what you want. It is sold at Autozone and other auto stores.

What I use on every connection in my car is conducting lubricant, which I bought in a small squeeze bottle from a local electrical supply house. Electricians use it on breakers and relays. It looks like it contains metal particles and you have to apply it only to the metal connectors, because it will conduct across plastic connectors if applied to them (as a friend of mine found out).

Hitch

Sorry Dave but dielectric grease is commonly used for these types of situations to prevent corrosion and to maintain a good signal path. Now I'm not saying that it's helping conduct but it prevents corrosion and that my friend is the biggest problem.. If you use a conducting grease if you are not VERY careful you will have LOTS more problems.. As your friend found out it will quickly cause a short circuit.. The main problem that I've seen with the bulkhead connections is that they are corroded and the pins have been flatten so that they no longer make a good connection. Also the tabs that hold the engine bay connectors to the fuse block break due to age... If you clean up the contacts/pins with a good electronic contact cleaner then follow up with a thin coat of dielectric grease you will have a lot less problems in the long run... Dave..

Just a follow up and some additional data that I pulled up...

"Two items that will help to improve electrical connections and avoid electrical problems are contact cleaner and dielectric grease. Contact cleaner and dielectric grease are nice to have when working on any vehicle.

Contact cleaner is available in many forms including standard liquid, spray and pen form. Spray contact cleaner is the most versatile and can often be used to get a power seat or other switches to work again without taking them apart. Small wire brushes or files can be used on connections with severe corrosion (Snap On's Blue Point division makes special round wire brushes to clean bulb sockets).

After using contact cleaner to clean electrical connections adding a dab of dielectric grease to every connection will help to make disassembly easier, prevent moisture buildup and reduce corrosion. Two major uses of dielectric grease are on light bulbs and on the ends of ignition wires (since it will also help to reduce voltage leaks from the system). Many major auto manufacturers (including Ford) actually include a small tube of dielectric grease with every set of ignition wires.

magicv8

Sorry Chuck, but conducting lubricant does every thing dielectric grease does and it promotes conductivity between contacts.

PS: Unless the manufacturer cannot use a dictionary, the dielectric grease actually makes electrical connection impossible.

PPS: Ball joint or wheel bearing lubricants are common dielectric greases. No use going to the store for more.

MasterDave

This is a fairly common issue. The whimpy little metal connectors will work fine in most cases, except for the main power which turns everything on. I didn't want to buy a new harness so I just found the
Big Red Wire' on both sides of the connector and spliced one (same ga. wire) to it, pushed it thru a hole in the firewall and spliced it on the inside. Have not had a problem in 3 years now.

JohnZ

To solve the corrosion problem inside the multiple connectors on the engine side of the fuse block, starting in 1968, GM (Packard Electric Division, the harness supplier) literally PACKED the two harness-side connectors with green dielectric grease; the guys on the line hated it because it made a mess when the connectors were installed on the fuse block, but it cured the long-term corrosion problems that plagued the 1967-and-earlier cars that had "dry" connectors.

wombvette

You got it Dave. Those whimpy little connectors trying to carry all of that load is the problem, and neither the Dieletric or Conductive grease , will solve the problem. You have to splice in a good path for the amount of power needed. Sorry John, but your penny pinching corporate decision makers always drop the ball on this one. These connectors are capable of handling 10A or so safely and are asked to pass 30-40 or even 60 with an air car. They get hot, loose their temper, and fail. This problem is probably the most common cause failure in any electrical device today from cars to computers and everything in between. Just this week I have repaired two C4 dashes with the lights out. Thats right, they are still up to their old habits today. I have repaired my heating system multiple times. Yes the same old problem. Oh, and there was the Electronic AC control on a C4 last week. Almost everything I see is related to this kind of problem.

Austin Aubinoe

Hi,

I know this is an old thread but I am having the same issues with my 1965 396 convertible. I was originally looking into the replacement bulkhead, but I have determined that one of the connectors is cracked, or a tab is broken off, so that it will not say seated.

My corvette will start up fine, but then sometimes nothing will get power (horn will still work). Then other times it will shut itself off when I turn the headlights on!
I am planning to unwrap all the wiring in the engine bay and take the time to inspect it, and wrap it with the proper tape. (Currently has vinyl electrical tape that has gotten hard.

My question for you guys is can I buy replacement plastic connectors and pins? Pretty sure my dash harness assembly and fusebox are just fine.

Thanks a lot, having a lot of trouble finding info on this!

Tampa Jerry

The wiring in your 65 is now 50 years old. I have read that the working life of the harness was to be no more than 15 years. If you are going to the trouble of removing, repairing and rewrapping the harness, why not just replace it? I replaced all of the wiring in my 66 coupe and my 70 SS Chevelle. The last thing I want is a dash fire. Good luck. Jerry

Austin Aubinoe

Yeah maybe I will. Just not in the fund at the moment. Working on restoring another truck and just trying to button this thing up in the meantime.

I have read that these connectors are called "Delco-packard" connectors, but I am not getting any results. To be clear, when I push the plastic connector (only one of them is coming loose) downwards, everything functions normally.

buns

They were formerly Packard, but are now Delphi Twin Locks. They are mostly made of Unobtanium. The people that manufacture wiring harnesses will not sell them to John Q Public. But they obviously have a source for new ones, and now we all do. Unfortunately, the minimum order is 2000 to 4000 units. Sure would be nice if a vendor could shell out a few thousand bucks and retail them.

This is a listing from Mouser Electronics, the only place I could find them after an exhaustive search.

.

Frankie the Fink

I would try the suggestion in post #4 above...
Sounds like you have typical "red wire" syndrome..

Austin Aubinoe

I still do not quite understand what this is, a bypass of some sort?

Thanks alot guys for the advise. I found this and seems like the right way to go. Is there a harness that is more authentic, or is this one pretty good?

http://www.mamotorworks.com/Corvette...block-697058-1

Or this (are these all made by the same people?)
http://www.ecklerscorvette.com/corve...96ci-1965.html

One more, better price. Why does it look like there is only one bulkhead connector? http://www.fullthrottlecorvette.com/...ck_p_2132.html

Frankie the Fink

Yes - it bypasses the fragile, corroded main power connectors at the bulkhead. Most here buy their wiring harnesses from Lectric Limited or M&H. Do NOT go for cheap in this area; you will more than pay for that decision with crappy parts or problematic installation. I would bet the big vendors source their harnesses from one or the other of these suppliers.

You can buy a bulkhead connector repair kit if that's your preference:

http://www.mamotorworks.com/corvette...r-kit-617746-1

Never rewired a C2 so I can't answer the single bulkhead connector question. Also spending $25 for the Dr. Rebuild laminated color schematics is one of the best expenditures you can make for your car:
http://docrebuild.com/oosoez/8964101.html

0Full Throttle Corvette

Austin, all of our harnesses come from Lectric Limited and are Correct reproductions of the originals. The reason for the single connector is that this is only the engine harness. The other connector at the back of the fuse block is for the forward lamp harness. If you have any questions on these, or other harnesses, give us a call at 770-978-0803. We keep most of these harnesses in stock.