'70 Cuda - several electrical issues (various lights) - need advice!

[wsr1961]

I picked up a 383 4 speed and there are several electrical issues. I printed out the electrical diagram and have a very limited understanding of electrical issues, but I think I can at least trace wires based on the diagram, to the extent they are reasonably stock set ups after 44 years! As a rookie, I will appreciate any insight you guys have, unless it results in me being electrocuted.

Here's what I have:

First, I also have a 1970 Challenger R/T, and each car has the 3-switch panel to the left of the rally gauges. However, the cuda also has 3 aftermarket indicator lights set in the dashboard. Two of them were not connected to anything and I removed them. I haven't checked the third one yet. I have no idea what purpose they served.

The dome light does not work. I touched the bulb outlet contacts with a circuit tester and the driver's door open, and sparks started flying where the tester touched the contact. I assume power is getting to the outlet but maybe there is a short? Any idea what I should do to try to repair it?

The fog lights are in the passenger floorboard along with about 5 feet each of wiring. They don't help much there. With the wiring diagram, should I be able to reinstall and connect them? Also, what makes them turn on/off? The headlight switch?

None of the fender lights/blinkers work. I frankly haven't even checked them for bulbs. I also have not tested any fuses. Should it be reasonably easy to get them working with the wiring diagram, even if I have to replace the outlets and/or wiring?

Headlights, tail lights, brake lights, emergency flashers, rear and front blinkers and reverse lights all work. However, when I use the right turn signal, the left tail light stops working while the right taillights are blinking. Any idea what that might be?

On an unrelated matter, I removed a valve cover to confirm head casting type and date. I noticed that the valve cover bolts were several different types, some with as many as 4 washers. Without confirming, I assumed they were a mis-matched set of various lengths with the washers used as spacers. So I ordered a set of Mopar big block valve cover bolts, and they also need the extra washers to fit tightly. The valve cover appears to be OEM stock. Is it possible that the thickness of the valve cover gasket is keeping the bolts from seating all the way, thus the need for extra washers? Plus I broke the head off of one of the mixed set of bolts tightening it. That's another problem I have to deal with. It protrudes a bit from the head but pliers won't turn it. I will try vise grips next I suppose.

If anybody wants to swing by and restore everything to factory stock that will be fine. I will even buy you a donut or two. Otherwise, any advice will be much appreciated.

 

[moparleo]

First thing to do is disconnect battery cables, negative first. Assemble an electrical contact cleaning kit ( electrical contact cleaner spray, fingernail emery boards, small ink erasers, electrical test light or a volt/ohm meter.) Also get a supply of high quality ( no Chinese or Taiwan junk ) Buss fuses, light bulbs ( get bulb numbers from old bulbs ) Dielectric grease.

Start from the beginning and work your way out. That way you will hopefully only do things once. Remove old fuses, and clean fuse connectors with emery boards, or eraser , install all new Buss fuses. Use the original recommended amp rating, most are 10 amp. Unplug harness from fuse block and check for burnt, damaged wires. Clean all connectors, apply dielectric grease and plug back in. Do this at each connecting point of the harness. Clean all light bulb sockets, Lightly grease and install new bulbs. Do not reconnect any non original wires. Mark and set aside. Do this on all connections including under dash, trunk, under hood, and harness in steering column ( must remove steering wheel ) It is very time consuming, but will solve 99 % of your electrical problems.

Start at the main harness/fuse block on the firewall behind steering column.

 

[moparleo]

As for your valve covers, you need to probe the depth of each hole will an ice pick, nail or whatever you have. This will determine if there are broken bolts in some of the holes. You will need good drill , quality bits and easyouts . Again, just take your time.

Have fun and good luck, it is a common problem on the electrical for all of us.

 

[wsr1961]

Moparleo,

Thanks. When I have enough time, I will do as you suggested. For now, I have a quick question about the dome light. When I remove the socket so that I can test the wires where they enter the socket, pink wire is drawing power, yellow is not. The same is true inside the socket on the two bulb contacts. When I add a bulb, it does not work but both wires show power where they enter the socket. Should adding the bulb create a flow through the yellow wire, or is my socket bad? If the flow is OK, then why doesn't the bulb work if drawing power? I have also tried a working bulb from my '70 Challenger, so it's not a bulb issue.

 

[moparleo]

Are you using a test light or a volt/ohm meter ?

 

[wsr1961]

Test light. I don't have the other. I bought the test light because power to the coil in my Challenger kept "disappearing". I traced the problem to the bulkhead connector, cleaned the contacts and hit them with dielectric grease. That's the only electrical experience I have. I had paid a restoration shop to fix that problem but it continued to occasionally not send power to the coil after they rewired all the connectors (or so I was told). I am proud of fixing that problem but, like I said, it is the only issue I ever worked on. I used a wiring diagram I printed online to trace the coil wire to the ignition switch.

And I know you didn't need to hear the Challenger story - but I thought it might be helpful to know that I am a total rookie but a stubborn one. If it will help, I will pick up a volt/ohm meter, as long as they aren't too expensive. I have two 1970s in the garage, no shop that I can depend on and the need to do it myself to the extent possible. I also had to correct a linkage error so my fast idle cam would engage after the licensed pros rebuilt my carb - something else I know nothing about.

 

[moparleo]

Harbor Freight usually gives the cheap volt/ohm meters away for free with a coupon in their add. They are only about $5-6. There is a problem if both wires are hot. Electricity flows from + to -. So there must be a short. A volt meter will tell you how much voltage is in the circuit.