70sWagoneers

Battery Cable Size/Routing/etc - '37 Special

Recommended Posts

Posted (edited)

1937 Buick Special 40 Trunkback Sedan

 

Hello,

I'd like to replace the autozone "replacement" battery cables on my car. The cables are incorrect and I suspect undersized. First of all, does anyone know what gauge the positive cable is? I'd like to use 2/0 as long as everything else looks factory correct. Is the 3/8" ring terminal to the starter bare copper or tinned copper (guessing bare)? Is the battery to chassis ground a cable or a strap like the starter to chassis ground strap? I would like to know if someone can show how the positive cable is routed from battery to starter as from the factory. As of now it is zip tied to the battery tray, then runs thru a frame brace hole and into the passenger box frame before shooting out perpendicular to the starter. As it is run now, it is about 60" long. If I look on Bob's Automobilia, their cable is 53" so perhaps my routing is incorrect. And lastly did '37 have a battery hold-down? Ive got the cover but just a bungee as a hold-down. I'll probably order from Rhode Island Wiring because I've used them a couple times before. I will also assemble the parts myself. So, in general, I'd like any info or pictures of the original positive and negative battery cables I can get.

Thanks

James C.

Edited by 70sWagoneers (see edit history)

Share this post


Link to post
Share on other sites

James,

When you get figured out just exactly what you need (and the guys on here will help you do that) you will want to get in contact with Bauer Electronics in Bend, Oregon.  They build wiring harnesses and battery cables for old vehicles.  They made new battery and ground cables for all three of my old Buicks.  The quality is excellent and they were reasonable with the price.  Hope that this will be of some help for you.

 

Terry Wiegand

South Hutchinson, Kansas

Share this post


Link to post
Share on other sites

James:

 On my 1937-41 I replaced the cables with ones from BOB's. And yes the positive cable is long!  The 53" is correct. I do wish I had them made up in a heavier gage. The web or strap type is correct for the ground. I had some excellent detailed photos of a well restored Maroon 37-41 that was for sale some years ago that showed the underside while up on a hoist. For the life of me I can not locate them now.

My battery box was non existent and has 2 steel straps and a board doing that job. I still need to fabricate another.In the parts book there should be reference to the box and hold downs. Possible Gary Wheeler will chime in with some info for you about his recent restoration of his 37. My car is in storage 3 blocks away or I could get better info for you.

DSCF5931.thumb.JPG.5724a12e8423a469bde9487ab35b0f1b.JPG

This is the only photo I have of my car have of anything close to the area.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Share this post


Link to post
Share on other sites
Posted (edited)

Hello James!

 

Here's how I routed my battery cables.  All my cables are size 1/0  and are also cloth covered.  I ordered them custom sizes with either battery stud clamp ends or rings depending on where I used them.  

 

 

2079721778_BuickBatteryCablesrouting.thumb.jpeg.044f2029ab26a8bd101d7e89df370de6.jpeg

Overview of my cables.

 I actually have two heavy cables coming off the  " - "  (Ground)  terminal because I'm a mental case and wanted to be sure I had the car grounded well.

 

 

DSC_0139.thumb.jpeg.455830402673e0c0b515aeeca406eb75.jpeg

I scraped all the POR-15 off the frame above and below the frame.

 

 

DSC_0439.thumb.jpeg.522d027970cf106e1707ddc36efcb92c.jpeg

That yellow shmutz is a corrosion-inhibiting battery paste.  I used star washers to give it mechanical "bite" into the frame as well.

So,  the yellow wire under the frame is a dedicated ground wire that runs back to the fuel tank sending unit.  I did cover it with a tar-impregnated cloth covering when it was installed.

 

 

DSC_0629.thumb.jpeg.385bbef5a82d091844a7fcf588aa218b.jpeg

One ground cable runs over to the top of that connection so the cable grounds the frame and the tank ground runs directly from that stud as well.

This cable was made with two eyes, the eyes are tinned.

 

 

DSC_4436.thumb.jpeg.f6825db18a03faf88a852690193affc5.jpeg

Here's how the ground to the frame looks like under the car.

All battery cables are cloth covered.

 

 

DSC_4443.thumb.jpeg.8e0273cd9a33235c4e3f4e818e7ca362.jpeg

That cloth covered wire clipped to the frame rail is the dedicated ground to the tank.

 

 

DSC_4428.thumb.jpeg.574c95fb81b2719730ea87cee8e63a2b.jpeg

The second cable off the negative side of the battery goes up to the starter grounding post.

This cable was made with a battery stud clamp on one side, an eye on the other.

 

 

DSC_4445.thumb.jpeg.96a5317967d17f3248ab8750b050d9c4.jpeg

I have that ground cable attached directly to the ground stud of the starter motor, and a braided ground strap runs from that stud over to the engine mount/side frame rail.

The other heavy cable is the hot wire.  I ran it through the opening in the engine casting to keep it stable.

 

I also ran ground wires to every single lamp on the car to be sure everything illuminated nicely.

Can you say overkill?

Can't help it.  

 

 

The only thing I did differently is installed a master kill switch just before the hot cable attaches to the starter.  

I really want to move that switch either under the dash, or somewhere else easier to access so I don't have to lift the hood every time I want to take her for a ride.

 

If you need any other photos or whatever.....  I got thousands!

 

Gary

 

 


 

Edited by Gary W
Battery Cable size is called 1/0. Not 1 (see edit history)
  • Like 3

Share this post


Link to post
Share on other sites

Nice, Gary. I've added a few extra grounds too. I added one from generator to chassis. So 1gauge spins the starter well? The starter is my main problem at the moment.

Thanks

James

Share this post


Link to post
Share on other sites

Plenty of juice to the starter.  She turns over fine and it's still a fresh overhaul...  still a little tight.  I have no problem adding a few extra grounds.  A lot of gremlins are caused by faulty grounds.

 

If I can help at all, please don't hesitate.

 

Gary

  • Like 1

Share this post


Link to post
Share on other sites
Posted (edited)

James,
As all the old timers here will tell you, 6 volt systems love big wires and good grounds.
When I did my '40 LTD, I used the braided ground, and 4/0 welding cable from the + side of the battery to the starter.
On mine, it was less than a 18" run from the battery to the starter.

I used the left over 4/0 also for a "jumper" from a bell housing bolt to the frame rail just under the battery tray.

Mike in Colorado

Edited by FLYER15015 (see edit history)
  • Like 2

Share this post


Link to post
Share on other sites

In a pinch, and if you are not caring about original appearance,  many tractor supply stores carry heavy gage battery cables.    They are all probably made in China,  but how badly can they screw up a simple battery cable.

Like Gary,  I am using an Optima 6v and am so much happier with it over the old style heavy battery that lasted about a year if you were lucky.

  • Like 2

Share this post


Link to post
Share on other sites

James,

 I just realized all my cables are size  1/0.   (Which is a size zero,  "one aught").   

I'm sorry for the confusion.  You originally stated you were going with the 2/0, and on 6V that's a good choice but these work nicely.

Share this post


Link to post
Share on other sites

Yes, 1/0 or 2/0 sounds like the way to go. My issue is starting. If my battery charger says 95% to full charge, I get about 20seconds total of cranking, and if she don't start, the battery is dead. And a lot of times, if everything is hot, the starter will barely turn the engine over. Ive taken any excess timing out of the distributor. Ive gone through the starter many times and have even changed out the armature which seemed to fix the problem for a while, but now I cant trust it again. The only thing left to change in  the starter is the field windings. But, I want to make sure the battery cables aren't causing me problems first (changing field is a pain). 

Thanks everyone.

James C

  • Like 1

Share this post


Link to post
Share on other sites

James,
Do you have an electric fuel pump mounted back at the tank (that's where they go) ?

Mine is on a toggle switch and it sure saves me a lot of cranking, when we take her out on weekends.

Also up here at 8500 feet, with no flat ground, vapor lock is a "way of life" and the electric pump sure comes in handy.

Just a thought.

Mike in frozen Colorado

  • Like 1

Share this post


Link to post
Share on other sites

James,

 

Mike is spot-on !

The same type of vapor lock conditions plague us here below sea level in steamy New Orleans' occasional summer heat -

or when we drive across Texas to visit western friends and family.

Each of our 6-Volt cars has either double or triple "0" battery cables, as well as a toggle-switched electric fuel pump,

mounted as low, and as close to the fuel tank as reasonable and safe.

Electric pumps work well when pushing fuel - far better than when pulling .

 

(Hello Mike - hope you and family are well and warm)

Share this post


Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...