1964 holiday rambler restoration /12 volt system problems

[The_rambler64]

First off hello, im new to rving and new to rv.net,and i need your help.
It all started when my wife wanted a camper. After much shopping a decieded they were overpriced and id rather restore a vintage model. After scouring craigslists and adds for a couple months we settled on a 1964 holiday rambler in very nice shape. We started by stripping everything on the inside to expose any soft spots which were repaired. I rebiult the entire plumbing system adding a hotwater tank and shower in the bathroom.
We stripped the entire outside aluminum it was in such great shape i ended up polishing 2' of it down the center and base coat clear coated the rest in a red , off white,turquoise paint scheme. Next all the aluminum windows were polished and restored with new cranks installed.

Next i tackled all the outside running and tail lights converting them all to led and installing a new 7 point plug in. Everything works perfect as intended.

The one thing the camper didnt have was a battery, the box was there but the wires had been removed. So i installed a brand new 12volt system with a glass matt battery and a 16 circuit fuse center . I added several new circiuts such as electric water pump, fan, usb chargers loft lights. They all function perfectly

Now im ready to reinsulate and panel the interior. Heres my problem the exsisting house lights they are original and each light has two bulbs and two switches . The 110 lights work perfectly when the rv is plugged into shore power. My problem is with the 12volt lights i cannot get them to work with the battery i must have something not quite right.
Heres what i know . I have one yellow wire(hot) that originally supplied power to all the inhouse lights, and one green wire providing the ground. When inspecting the light fixtures i find the neutral wire for the 12 volt light is placed into awire nut that houses the ground for the 110 light. This is found the same way on each light..

So heres what i did. I ran a ground wire from the 2 breaker panel to the battery ground, then i spliced into the exsisting yellow power wire and ran that to my 16 fuse center to supply power from the battery. All i get is a barley glowing filiment inside the bulb.
I would love some direction or ideas on what my problem is
Thanks guys

[azrving]

The rambler64 wrote:
Awesome im trying to sort it out now-seperating both grounds and attatchingbthembto the trailer frame... right?

Whats the easiest way to post pictures? I looks complicated.. thanks again guys

As I read your post I kept thinking this guy needs to post pics. 🙂

Use this

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Paste it directly on your thread

[enblethen]

Do not confuse the 120 volt neutral and ground. There are different.
The green or bare wire in the 120 volt system should be connected to the rig's frame as a safety ground.
The white wire in the 120 volt system is the neutral. It should not be connected to the frame or DC system.
Look at some of the 12 volt DC lights. The shell of the lamp socket should be the ground. Check color of the wire.

[The_rambler64]

Awesome im trying to sort it out now-seperating both grounds and attatchingbthembto the trailer frame... right?

Whats the easiest way to post pictures? I looks complicated.. thanks again guys

[Artum_Snowbird]

With a little calculation and an estimate.. A normal interior bulb takes about an amp. That makes 12 watts at nomimal 12 volts. Likely a faint glow would be only one watt.

What happens? Well, instead of having a single bulb getting power through the filament to negative ground, power is not finding it's way back on the ground. Power then goes out and finds it's way back through another filament. You still have 12 volts in the circuit, but voltage drop to produce one watt would be around 3.5 volts at that bulb, and the other 8.5 volts is dropped somewhere else.

As others have said, you need to not only provide power, but also be sure every ground and negative return is connected.

[ScottG]

I agree, separate the grounds.
Also, those old 12V lights draw a ton of power. LED fixtures are pretty cheap on eBay and you could run a whole house worth for less than the power needed for one of the original bulbs.
BTW, we would really enjoy seeing pics of your project!

[donn0128]

Add a seperate ground for 12 and 120 volts. IMHO its not really sound practice to ground both circuits thru the same wire. I suspect your problem stems from the 120 ground and the battery ground are not on the same path. Since everything is open it should be a simple matter to test. Run a dedicated wire from the battery - to the ground side of a light fixture and turn the bulb on.