So my '70 Skylark has a loose headlight connector that can sometimes go dim until you fiddle with it and reestablish better electrical contact. I believe I can replace just the one connector but I'm curious from those who have done this job of replacing the entire headlight harness how difficult it is. It looks like a relatively simple job but I'm curious how the bulkhead connector detaches from the firewall. Is it held on with fasteners or does it plug or snap on? My car is in winter storage at the moment so I can't just go out and look at it, and the photo of the new harness on the American Autowire website doesn't show that detail.
You will need either a 1/4 or 5/16 nut driver to take the center bolt off the fuse block to remove the plugs for both the engine harness and the headlight harness. The plastic clips that hold the harness to the fender and radiator support are a little fragile, being they are plastic and 5o plus years old. You MAY be able to remove the clips but I recommend getting new ones from Todd at Diecast Collectibles/Stagewonrestoration .com. It is an easy peasy job. Hardest part will be moving your battery to access the passenger headlights.
I am ocd and made my harness from scratch each wire individually. it’s very easy to do, just undo the bolt at the firewall Fusebox and it slides out on my 68 at least. Then I used pliers to squeeze the Packard 56 terminals tips to remove each one individually to clean/replace. I did have to buy Packard 56 terminals and the special tool (finding one was the hardest part about the project).
If the only problem you are having is just that one headlamp and or socket, just get a replacement socket/ pigtail and splice it in, or simply get a few Packard / Delphi type 56 female wire terminals. Use a VERY small flat screwdriver or jeweler's screwdriver to release the tab from the socket. You may also have a loose terminal on the lamp itself (This happened to me several years ago.)
For a car frequently driven at night I'd recommend adding relays to power the headlights. There are all sorts of plug and play kits now that don't require hacking up your original harness, plus it takes all the load off that old wiring and headlight switch. I decided to try it out after realizing the headlights in my 67 GS would flicker or shut off entirely if I used the highbeams for too long. This doesn't fix your bad connector, but might be a good idea while you are already in there. This kit technically only requires one of the three prong plugs from the stock harness for it to function, so you could always leave the intermittent one alone if you chose. OCTANE LIGHTING 4-Headlight Relay Wiring Harness H4 Headlamp Light Bulb Ceramic Socket Plugs Set https://a.co/d/dWABXv2 Of course it is easy enough to make your own relay harness if you want to save a few bucks, but I have a feeling it would be tough to beat that price once all is said and done.
I also recommend the relays... It removes the HEAT at the headlight switch. The factory wiring has been known to actually melt the harness to the headlight switch... https://www.danielsternlighting.com/tech/relays/relays.html
I may end up doing exactly that This car is not often driven at night. The high beams are rarely used, maybe once or twice a season and theres usually just enough oncoming traffic that I don't have to keep them on for more than a minute or so at a time Is this an occurrence with all four bulbs on or can it happen with only the headlights on? $$$$$ I may make that upgrade in the future, but it's not gonna happen this year.
Is this an occurrence with all four bulbs on or can it happen with only the headlights on? The melting to to each other... ???????????? I know I needed a screwdriver more than once to separate the harness from the switch more than twice.. other times they come right off,,,, One truck the two would not separate wasn't worth fixing used it for parts ... Seeing how they were all used cars I have no idea how the lights were used by former driver...
I've never heard of anything in the headlight switch or harness melting before, if others have heard of this I wonder if it ever happens in cars that rarely use the high beams or if it ONLY happens with cars that often use high beams. Or maybe there is no correlation.
Oh yeah, headlight switch and ignition switch. I've seen both. Turn on your interior lights, turn on the headlights and high beams. Then reach up and hold your hand on that light switch. It'l warm up.
Headlight relay info on this site is on the weak side......Some one is always pushing those POS led lights...........Get in to a old school truck forum relays are heavily pushed. Led's are looked down upon. Here's the relays that I recommend only for the fact they state the 14 gauge wire..... https://www.ebay.com/itm/115209801149?_trkparms=amclksrc=ITM&aid=777008&algo=PERSONAL.TOPIC&ao=1&asc=20230811125216&meid=abff58aa21d74ee68b39fc3175311d9f&pid=101771&rk=1&rkt=1&mehot=none&itm=115209801149&pmt=0&noa=1&pg=4375194&algv=WatchlistVariantWithMLR&brand=Nokya&_trksid=p4375194.c101771.m47999&_trkparms=parentrq:afde6bf818d0ad93153cb8dafffff65a|pageci:f3eb9089-cc77-11ee-9cde-020fdb6e9714|iid:1|vlpname:vlp_homepage
When you post a very long eBay link, you can skip the https:// part and the question mark + everything behind it www.ebay.com/itm/115209801149
If I was the OP, I'd remove the terminals from the plastic connector and use a Dremel wire wheel on them. Zero dollars and would probably fix the issue
Ter Terminals build up corrosion, bad grounds degraded wiring, the headlight switch contacts and the rheostat (especially having the dash lights turned down/dimmed) all add up to a great deal of resistance, and wire fire. And when it happens it happens fast, and if the fuse links have been "deleted" (and in 60 years and several owners...) there is little you can do if you can't get the battery disconnected.
I first ran it on a burned up harness/lightswitch was in a 69 chevelle wagon in about 1982.. It's electrical it happens all the time......
WTF is your problem.... You need to look at yourself first before you look at others.... DO me and the rest of the world a huge favor hit the ignore button.....
Bob - Seems like Nailhead was just trying to be helpful. But I don't know your relationship - maybe theres more to it. I do question your comment on POS led headlights? Mine were inexpensive, 2X brighter than my stock lights, use less current, and have a nice cut line. Again, I don't know your experience with them, but my experience is excellent.
