Electrical / Rewiring - some questions

[boxer_inv]

Hi to all again, time for some more 'noobie' questions...

First up, I've searched the heck out of this forum on this topic and I've answered way more questions myself than I'm hopefully going to have to ask! There is some exceptional advice on re-wiring jobs on the forum - belated thanks to those who've shared their knowledge previously.

Okay - "Dorothy" is running nicely at the moment overall, just some minor things that i'm wanting to deal with.

• Instrument lights are not working
  
  
• Many cables and wires have seen better days
  
  
• Thinking of different brake light/indicator setup for the rear end, for safety.
  
  

I'll deal with each...

1. Instrument Lights
   

They don't go. Have been under the dash with the multimeter, pulled all of the bulbs, housings etc. Bulbs aren't blown as they seem okay visually and register resistance on the meter. Can't seem to get anything like 6V power reading from the housing or wires, and can't find where its either shorted/grounded, or broken.

The wiring in behind the dash is old (who'd have thought?!). Needs attention.

• Battery Leads + Others
  

Here are a couple of pics of my battery cables as they now look. I could be just dreaming this up, but I'm thinking that its only a matter of time before this one shorts out completely and sends me or the system up in smoke...

• Brake / Indicator light setup
  

It hasn't taken much time driving around to discover that most people have never seen blinking red 'brake' lights as indicators before - least not here in Far Northern Australia. Also, like others on here have commented before, I've had people tell me my brake lights aren't working (when i KNOW the centre one is).

So I'm wondering whether alterations to the original setup is worthwhile.

HERE'S THE QUESTIONS:

I think that Dorothy probably deserves to have a re-wire job (kinda like taking the varicose veins out of an old girl...).

I've read some people do the re-wire job - 1 wire at a time where everything remains in-situ. Others have done the re-wire by removing the entire harness, pegging it out on a board and then assembling a new harness to match. IS THERE ANY CLEAR WINNER AS TO WHICH METHOD IS BETTER??

I've got the Dodge Shop Manual with the wiring diagram, but this doesn't indicate wire size or colour. I've read some of you have this type of wiring schematic in your manuals. Can anyone advise of WHICH MANUAL I SHOULD OBTAIN, besides the one i have, and which has the wiring details?

I've come across this AUSSIE based outfit that appears to do a harness for a D-24.... http://www.vinwire.com.au/bcd_list.htm...though it's at some cost. Actually, a lot of cost.

Lastly, I've read the pro's & con's of changing from 6volt to 12volt. I'm sticking to 6v unless anyone really has a decent case to wage and can CONVINCE ME TO CHANGE? I'm not running any modern accessories and don't plan to.

Sorry this has turned out so long-winded, but hey, you guys got nothing better to do, huh?!

Rob

(The OTHER Aussie)

[Young Ed]

I pulled the main harness's out of my car and redid them. It took me about 3 weeks for the entire project. What I did though was pull the entire dash with the harness attached. I labeled all the items I had to remove from the engine etc. Then I labeled the few dash ones I had to unplug after I had the dash out. Much easier to see stuff this way. Part of the reason I did it this way was that I was also putting in a newly painted dash. I still haven't redone my wires to the back or the pigtails for the head and parking lights but all the engine and under dash wiring is new. For the sake of buying less wire I changed everything that was 16g to 14. Most of it is 14 with some 12 10 and I think 1 8 gauge wire.

[Plymouthy Adams]

do you still have the dash light dimmerswitch for the on your car? and if so is it on and making contact through the switch....?

Do upgrade them cables..the ground side is not that critical but the supply side..you don't want to imagine the amperage these things will conduct before ever thinking about burning through..suggest 00 or at minimum 0 size cable

rear brake indicator is very important to prevent a rear end collision..it is best in my opinion if you are not against some change is to wire the three rear lights to come on with the application of brakes..

If you are simply wanting to upgrade your wiring to a safe reliable unit and not concerned with it being stock cloth covered..then a one by one would do well but if you photograph and tag the ends and remove the harness..building a complete duplicate and re-installing would not be hard..a harness is nothing more than individual circuits along a common path taped toether. Factory similar duplicate harness are outrageous priced..try 750.00 for an original duplicate..

as for the call to 12 volts..if you have no concern to run modern devices and your charging system is in good order..why mess with prosperity..stay 6. proper guage, clean grounds ..you be ok...

[Jacqualine47]

EDIT: On my diagram, just superimpose 6v over 12v, it'll all work the same... and you don't have to use fuses since the original didn't - I just love to fuse all my circuits

Personally, I'm planning on redesigning the entire electrical system - however, that's totally not necessary and I don't recommend it (I'm just a bit nutty)

However, I can help with your current problems... first off, here is a wiring diagram (I found it on this forum where some other kind soul put it up, so I take no credit) for the car:

For your turn signal and brake lights, here is the wiring diagram I'm planning on using (it uses the original switch, makes the front parking lights into turn signals as well as parking lights, makes the rear lights both turn signal and brake lights while keeping the center brake light, and adds emergency flasher functionality) - it is one I took from HAMB and altered with the correct blade numbers for the DPDT (Double Post Double Throw relay, you can get them on Amazon.com rated at 20amps for about 10 dollars apiece) and added a switch for emergency flashers.

If you don't want to use the DPDT relays, I'll happily tell you how to instead use four standard relays from parts express.

Now, for a quick temporary fix for the instrument lights, just pick up a standard relay (I recommend Parts Express as a source: www.partsexpress.com - they also have free wiring diagrams and tutorials on how relays work and are wired) and wire it so that it is triggered by the headlights being on, and send a fresh hot wire to the gauge lights.

As for going to 12v... I recommend AGAINST it. The only reason I'm doing it is so that I can run a bunch of modern stuff like an MSD ignition, electronic cooling fan, etc. If your 6v system works, then keep it.

Hope that helps.

Edited September 9, 2009 by Jacqualine47

[Frank Elder]

Don't bother looking for your rear harness under the floor mat like on a newer car....that rascal is above the headliner and cinched down tight! You can't just fish it out, it will require a partial pull down...windlace and liner plus your dome light,DL switch etc.

PS. If you want your front parking lites to stay on when you turn on your headlites just take that wire off its connection and add it to the head lite connection.

Edited September 9, 2009 by FRANKIE47

[Young Ed]

I've been thinking of moving mine to under the flooring when I rewire the back lights. My 51 has the wiring on the floor

[boxer_inv]

do you still have the dash light dimmerswitch for the on your car? and if so is it on and making contact through the switch....?

As far as I have seen, the instrument lights are still running through this switch. Tried it with this switch in both positions, bypassed it, pushed it, pulled it, prodded it.....nothing.

Do upgrade them cables..the ground side is not that critical but the supply side..you don't want to imagine the amperage these things will conduct before ever thinking about burning through..suggest 00 or at minimum 0 size cable

Any idea on what amps most of the circuits in the car actually pull?

rear brake indicator is very important to prevent a rear end collision..it is best in my opinion if you are not against some change is to wire the three rear lights to come on with the application of brakes..

Not against change at all. And that goes for 'stock' or 'original' wiring - I'm quite certain that I won't be aiming to have Dorothy judged at car shows, shes just for pleasure, so not having cloth covered wiring won't bug me at all, and sure as heck the cost saving will make me happier.

Rob

[boxer_inv]

EDIT: On my diagram, just superimpose 6v over 12v, it'll all work the same... and you don't have to use fuses since the original didn't - I just love to fuse all my circuits

I'm inclined to do the same if re-wiring.

first off, here is a wiring diagram (I found it on this forum where some other kind soul put it up, so I take no credit) for the car:

Thank you!! I recall seeing these photographs before, but do you think I could find them again?! Oh, the wonderful mysteries of the search function....

Actually, every time I discover a good thread now, I'm saving the information to a folder. One of the other members described doing this (can't recall who - but kudos to them and thanks) and it is a good idea.

Tim Adams / Greg G et-al, can you comment on the Manuals that might serve me better, other than the one I have?

Rob

[Plymouthy Adams]

on the dash light switch, have you tested this with a test light/volt meter for power to and through the switch?

As for current..each circuit as activated and jointly activated is the total draw of the the system..say for instance the high beams are 45 Watt times two (left and right) is 90watts divided by 7.2 volts (total good output of generator) is roughly/approximately 12.5 amps..and that is just the headlamps throw in a bit more for the parking lights, front lights and dash lights. This is the reason the wires size is of such importance in 6 volt systems..lighting circuit is protected by 30 amps fuse

most ignitions circuits will probalby pull about 2.25 amps running, 5 amps stopped (key on) horns, according to model from factory can be up to 30 odd amps thats a killer and that the reason for the relay...

starter however is pulling 280 amps..radio is fused at 14 amps..

these are just a few and some are as marked by fuse ratings and not the actual draw..safety fused at usually twice the actual..

other may add what they know for fact..

[Plymouthy Adams]

I have the 46-54 Plymouth service manual and find the info quite helpful but you will have to search the sections for some of the actual current data..

IF you are upgrading to 12 then use the fuse chart for the donor car for proper fusing and wire selection...the AWG charts available on the internet will state the size wire needed for x voltage for x feet of run..very helpful when building your own harness with a multitude of power options like power windows, seats, door lock poppers, AC, cooling fan and the list is limited only by your need or desire to option..

Edited September 9, 2009 by Tim Adams

[Don Coatney]

Under (not behind) your dash board you will find this pictured toggle switch to the right of the steering column. This is your dash light switch. Some have 3 positions (dim, dimmer, and off) some have two. (dimmer and off).

[boxer_inv]

Under (not behind) your dash board you will find this pictured toggle switch to the right of the steering column. This is your dash light switch. Some have 3 positions (dim, dimmer, and off) some have two. (dimmer and off).

Don - nup. Not under/behind/on or in my dash is there such a toggle as that. Have I been short changed?????!!!

I had thought that one of the 2 switches on either side of the centre light (above the ignition key) was the instrument light switch. As they didn't work, I wasn't sure... is this incorrect?

Tim - thanks for that info regarding amps - I knew that the 6v system was capable of drawing some serious power - that confirms it!

Rob.

[Andydodge]

Rob......have you had a good look at your headlight switch?..........reason I ask is that there maybe a power source and hence a wire from your headlight switch straight to the dash lights OR a switch that controls them.........my 1940 Dodge had a switch like that shown in Dons pic under the right hand side of the dash, near the handbrake or above it......anyway if you don't, have you checked that all the bulb sockets for the dash are present?.......there should be 3-4 which should include one for a bracket that goes onto the ignition switch to light it up and then 2-3 sockets that push into the instrument cluster.......if you have all the sockets, either run a wire direct from the headlight wire from the headlight switch to all these sockets.......then when the headlight switch is on so is the dash lights......also one thing you might want to keep in mind is that your car being RHD may have a slightly different dash switch layout to the yanks........ie, we have a key ignition and STARTER BUTTON on the dash........the yanks didn't have that.......they had a foot starter, also we have, or should have electric wipers.......have you a couple of pics of the dash layout you could post as that may help( I'm not 100% clued up on post war dashboards)......I have attached pics of the dashboards of my Dodge & Plymouth....how does your layout compare? ......btw as far as comapring 6 to 12 volts, if everything in your 6 volt system is 100% then 6volts are fine, but to be honest, 12 volts to me is a much easier setup.......but to each our own......andyd.

[Andydodge]

Rob........not to be blunt but I'd throw those battery cables to the shithouse.......you are just asking for trouble keeping them on the car, or just invest in some BBQ forks and have them ready for when it goes..........wooosh....seriously tho, replace them asap, we'll all feel much better........lol.........also using brake lights for indicators here in Oz is just asking for some rear end action.......lol........orange motorbike blinkers might not be original but at least the moron behind me can see me.......and check the brake light reflectors for reflectiveness(is that a word?....lol)......pull the light sockets, clean them, spray white, then pull the lens etc out and clean it up.......and spray the body around where the reflector pushes thru white or silver.......that workshop manual should be o/k, for general work.......there is a 1946-1953 Australian factory Workshop manual but I doubt whether its any better than that US export copy........I have an Oz one if you want specific stuff copied ......andyd

[Frank Elder]

Don - nup. Not under/behind/on or in my dash is there such a toggle as that. Have I been short changed?????!!!:pRob.

No, you haven't that toggle, it is not on my D-24,Our dimmer switch is the right hand knob under the speaker...p-15 has the toggle switch.

Edited September 10, 2009 by FRANKIE47

[Frank Elder]

Panel light switch. When I first say your profile picture I was suprised to see you had a d-24 instead of the canada model, I wonder how it got exported......

Edited September 10, 2009 by FRANKIE47

[boxer_inv]

.......have you a couple of pics of the dash layout you could post as that may help( I'm not 100% clued up on post war dashboards)......I have attached pics of the dashboards of my Dodge & Plymouth....how does your layout compare? ......

Couple of photos of my dash layout. Typical D-24 as far as I can tell, just mirrored RHD from the LHD

[Young Ed]

Hey Tim there's more of your black dash knobs

[boxer_inv]

Panel light switch. When I first say your profile picture I was suprised to see you had a d-24 instead of the canada model, I wonder how it got exported......

Yep - true RHD D24, NOT D25.

The original New Zealand registration paper (from 1955) which I have indicates it was imported from Malaya. This could have been Singapore, or one of the other Malay states at that time...unknown which exactly.

I've never seen or heard of another RHD D24 on this site - or have I missed them? D25's, yes - RobertKB's being a good example in Canada, but also some over here in OZ, which I think are the Richards' body examples.

[Andydodge]

Rob, forget what I said about getting an Oz workshop manual, you'll be best to stick with that US export one, nice dash btw...........are those battery cables replaced yet?.......lol........btw your car would be quite rare here in Oz, you mention it coming from Malaya which would account for its being the real deal, nice car.......regards, andyd

[Frank Elder]

Couple of photos of my dash layout. Typical D-24 as far as I can tell, just mirrored RHD from the LHD

Your dash is light colored like a p-15 woodgrain and your brake and clutch pedals are different than mine.Here are pictures of my pedals and dash color.

[Plymouthy Adams]

Hey Tim there's more of your black dash knobs

Sure enough Ed..there are export Specials, as the special knob/cable molded assemblies were listed in the book for RHD part numbers...

[boxer_inv]

Rob........not to be blunt but I'd throw those battery cables to the shithouse.......you are just asking for trouble keeping them on the car, or just invest in some BBQ forks and have them ready for when it goes..........wooosh....seriously tho, replace them asap, we'll all feel much better

Andy

Pleased to report I now have new battery cables installed! You can now rest easy...

Young fellow at the auto electrician's said to me "how big??!!" when I asked for that size - could have been the first time he'd heard of 6volt... The old bloke came over and said - "yep, bigger the better, no worries mater we'll make some up for you".

I'm now taking 2 weeks off work for a much overdue holiday. Start on the re-wiring job tomorrow and looking forward to it.

No doubt I'll be updating with further questions as I progress...

Rob

(The OTHER Aussie)

[Plymouthy Adams]

go for it..not that bad a job..after the headstands under the dash..rest is a breeze

[n1gzd_plymouth]

When I bought my Buick it came with an uninstalled $600 front wiring harness (everything under the panel and under the hood) that the previous owner was afraid to tackle. It was from Rhode Island Wire (Massachusetts). In installed this myself on a 95 degree day and finished most of the work in one day (probably should say it was a weekend job but the bulk of it was one day).

Rhode Island Wire makes really nice looking stuff for stock installations. They have a long list of harness but they never make anything from diagrams (the first one that they make they want to have a real example to copy so someone has to send them one). This means that for less common cars they might not have it (but they might have one for another model for the same year and make that is very similar).

When I replaced this harness I completely cut off the old harness at the firewall but left the wires connected under the panel. I did a similar thing in other places. The old wire color codes and sizes were still identifiable if you compare them to the new one (which used the exact same colors). So I just changed the wires one by one (removed the old ones one by one as I added the new ones). I did testing with my ohm meter along the way to make sure that things worked. I found three mistakes in the harness that were just wrong terminal (wires were all correct).

Surprisingly everything worked perfectly when I connected it to the battery for the first time (but I tested it carefully).

I need weak reading glasses (1.0) for arms length stuff but I have found that when you are working under the panel you are forced to have your face only inches from stuff. I use 3.0 reading glasses for this and it works fine.

You will need standard tools for electrical work, a multi-meter, curcuit diagrams (for QA),and wire lists that come with the kit (to inventory words and terminals before you start and to check them off after you connect and test them).

Here are some pictures. They are self explanatory (show what wire looks like, tools needed, work environment, paperwork that came with it etc). Sorry it is a Buick but the same work for any car:

http://www.pangalacticconsortium.com/cars/Buick/imgpages/image049.html

http://www.pangalacticconsortium.com/cars/Buick/imgpages/image053.html

http://www.pangalacticconsortium.com/cars/Buick/imgpages/image054.html

http://www.pangalacticconsortium.com/cars/Buick/imgpages/image055.html

http://www.pangalacticconsortium.com/cars/Buick/imgpages/image056.html

http://www.pangalacticconsortium.com/cars/Buick/imgpages/image057.html

http://www.pangalacticconsortium.com/cars/Buick/imgpages/image058.html

http://www.pangalacticconsortium.com/cars/Buick/imgpages/image061.html

http://www.pangalacticconsortium.com/cars/Buick/imgpages/image062.html

http://www.pangalacticconsortium.com/cars/Buick/imgpages/image063.html

http://www.pangalacticconsortium.com/cars/Buick/imgpages/image064.html

http://www.pangalacticconsortium.com/cars/Buick/imgpages/image065.html

http://www.pangalacticconsortium.com/cars/Buick/imgpages/image066.html

http://www.pangalacticconsortium.com/cars/Buick/imgpages/image067.html

In this picture you can see the old harness chopped off at the firewall and the harness being routed in. On this car some of the work can be done from outside but you still have to crawl under the panel for a lot of it:

http://www.pangalacticconsortium.com/cars/Buick/imgpages/image043.html

I did not just blindly copy the old wires, I checked the diagrams and identified everything first but having the old wires still connected provided more information to cross reference. that was the key thing. always cross reference each connection with a couple of sources and then you be very sure that it is correct. doing this is pretty easy.

Rebecca

Edited September 25, 2009 by n1gzd_plymouth