Electrical: updating to 12 volt, lights

[Timothy Barr]

I have a 48 Land Cruiser and updating to a 12 volt system. I am using the Randall book but finding the right bulbs for 12 volt has been some research. Called Studebaker West about how to find the right bulbs for the entire vehicle. The vehicle is all apart and looking to get it back together this summer (Prayers for the Body man). The guy at Studebaker west said that the tail lights, I will need to change the little knubs to from the offset to the equal distant knubs. Seems like a lot of work. Was thinking of replacing the rear sockets to a more modern ones, possibly the ones from the 50s. I am thinking it may fit in the hole of the light housing, but not sure. Also want to make sure the ground set-up would be the same. Want to make everything easy to convert back to 6 volt. Anybody know anything about this?
Think i have found the interior bulbs, but cannot test them yet until i get everything changed over.

[studegary]

I question the "updating" part. True, the 12 volt system is newer than the six volt system. That does not automatically make it better for your application. Your car will operate fine with a six volt system in good shape. What is the reason for going through all of the trouble, work, expense of the conversion? If you are modifying the car with air conditioning, I can understand (but not agree with) the change.

[BobPalma]

What Gary said, Tim; it is usually inadvisable to "improve" a 6-volt, positive-ground car to 12 volts, negative ground.

The car operated fine its entire life on six volts. With today's battery technology and the correct heavy 6-volt battery cables, you are far better off to restore it as designed. Honest, Studebaker's electrical engineers knew more about automotive electrics in 1946, when the car was being designed, than you or I will ever know.

This is especially true now that the car is dismantled. You'll have enough challenges figuring out how everything goes back together as it was originally assembled, much less complicating matters with such a proposed change.

Seriously, I've been Turning Wheels' Technical Editor 35-odd(?) years. If I had a dollar for every question the Advisors have fielded about straightening out every six-volt Studebaker that was "improved" to 12-volt electrics, I'd be able to have supper at Cracker Barrel every night for a year....well, OK; at least a month.

Proceed if you like, but this thread will always be here to remind you of the preferred approach to the car's electrics when and if you become frustrated with the electrics not working properly when you're trying to enjoy it. Please reconsider. BP

[1954khardtop]

I went through this with my '54, and found the following 12 volt bulbs that worked in my original sockets. If your '48 uses the same 6 volt bulbs this should work for you.

[rockne10]

The only reasonable reason to convert would be to operate air conditioner or stereo. Still substantial work unless your antique is going to be your daily driver.

[altair]

I have a 54 sedan with a 6 volt system and I installed a '63 259 V8 (12 volt engine) and converted it over to 6 volts and it starts up sharply and runs well. My reserve option was to run the engine on 12 volts and charge the 12 volt battery from an external source. I would not have considered converting the vehicle over to 12 volts, too many issues.

[mbstude]

Air conditioning can be added to a 6 volt Stude, too.

[Ross]

This winter the 50 Champion is the daily driver--and I do mean daily. By the simple expedient of changing the oil from its usual 15W40 to 10w40 for the cold weather it has started every time even down to -5. Yes it is 6v and has the cheapest battery from Tractor Supply. When I got the car I freshened up the battery cables and the headlight wiring as the mice had been busy. It is all really quite satifsactory.

[Jeff_H]

So,

Here is some info I saved from 2001 that came from Gordon Richmond (on this forum as well) that was posted to the old alt.autos.studebaker news group back when. I had to go look on a portable backup hard drive to find this stuff:

I found an old Lafayette Radio catalog (1965) and a 1966 Chryco All-Make
parts catalog.

I'll list some bulbs that may be relevant to Studebaker. Anyone wanting
a scan of a catalog page, e-mail me. I will try to list 6 volt bulbs in
pairs with their 12 volt counterparts.

Miniature bayonet base bulbs (dash lamps):
G 3 1/2 are the small round bulbs, G 4 1/2 are a bit bigger, T 3 1/4 are
the elongated cylindrical bulbs
Bulb# Volts Candle power Globe type Remarks
51 6 1 G 3 1/2 dash bulb
53 12 1 " " "

55 6 2 G 4 1/2 " "
57 12 2 " " "

44 6 0.25A T 3 1/4 radio pilot lamp
47 6 0.15A " " " "
1815 12 0.2A " dash bulb
1847 6 0.15A " " "
1891 12 0.24A/2CP " " "
53 14.4 0.12A G 3 1/2 " "
1445 12-16 0.7CP G 3 1/2 " "
1488 14 0.15A T 3 1/4 " "
1813 14.4 0.1A " " "
1815 12-16 0.2 " " "
1816 13 0.33A " " "

That's about it for dash-size lamps. #51 is, I think, the one used in
the Studie "black light" instrument panels. The #55, I think, has too
big a globe to fit. As far as I can see, there is no brighter bulb than
#51 for this application, unless maybe you were to put the globe of a
PR-12 flashlight bulb into the bayonet base of a #51. They rated 0.5A at
5.95 volts, or about twice the wattage of a #51. Project for somebody?

Single-filament bulbs for dome, park, tail, etc. Bayonet base, the
common auto size:
Bulb# Volts CP/amps Bulb shape Remarks
63 6 3CP small round park, licence?
67 12 3CP " " " "

68 12-16 4CP " " double contact base, dome?

81 6 6CP " " park, licence
89 12 6CP " " " "

82 6 6CP " " d.c. base, dome or courtesy
90 12 6CP " " " " " " "

87 6 15CP S8 (like #1034) parking??
93 12-16 15CP " " "

88 6 15CP " d.c. base, courtesy?
94 12-16 15CP " " " "

209 6 15CP B6 (skinny pear) dome, single contact
1003 12 15CP " " " " " "

210 6 15CP " " " d.c. dome, courtesy
1004 12 15CP " " " " " "

1154 6 21/3CP S8 tail/stop combo
1034 12 32/4CP " " " "

1158* 6 21/3CP " " " "
1157A 12 32/4CP " " " "

1129 6 21CP " stop, backup
1073 12 32CP " " "

1095 12 14CP " " " ?
1034A 12 14CP " d.c. base
1130 6 21CP " " "
1141 12 21CP " stop, backup
1142 12 21CP " d.c. base

1155 12 3CP S8? tail, park, licence?
1156 12 32CP S8 backup, stop
1176 12 21CP " d.c. base

This pretty well covers the dome and/or exterior lamps. I think #1156 is
the common stop/tail bulb for 6 volt Studebakers. #1158, I think, has
either reversed connections, or else a base with 2 equal, not staggered
bayonet pins. Seems to me there is a "ringer" in the 1034/1157 camp,
too, but I don't have the number. Most of the ones with double contacts
(d.c. base) have no connection to the shell, useful when the circuit si
switched on the ground leg, like a dome light. I left out some oddballs,
like fog or headlamp bulbs.

Hope this will be useful, and that the tabs don't mess up.

Gordon Richmond
There ought to be a bulb on this list for most any application in a
post-war Studebaker, EXCEPT for fog lamps.

This was formatted with tabs so comes through a bit mashed up but you should be able to copy/paste into a document and fix it to make easier to read the alternates.

My '53 is "resto-modded" and is 12v. So, I used the info above to change out the dash lighting. For the front/rear signals I replaced the sockets and used 1157 type bulbs. The whole car was rewired etc so not concerned about that part.

[bensherb]

I don't understand the fear and terror of changing from 6 volts to 12 volts. I've changed over several cars from many makers, both positive and negative ground and have never found it to be difficult at all. The only real consideration needed is when retaining the 6v radio and fuel gauge, and they are easily taken care of with a resistor and regulator.

[TWChamp]

I wouldn't call it a fear of changing, but do think of it as an unnecessary change.
6 volts works great and saves money from doing the change.
I run an insulated lighter socket to use for charging my cell phone and running my GPS. Both work great on 6 volts.

[DWBookout]

I run a separate isolated circuit from a deep cycle 12-VDC battery for a CD/DVD/Radio and GPS. That's interesting about using 6-volt for GPS and Phone. Will have to try it with an old GPS that is no longer being used. I installed a 6 Volt alternator and that makes all the difference in everything electrical. it keeps charging the battery right up to the last second and the lights no longer go dim at idle.

I wouldn't call it a fear of changing, but do think of it as an unnecessary change.
6 volts works great and saves money from doing the change.
I run an insulated lighter socket to use for charging my cell phone and running my GPS. Both work great on 6 volts.

[bensherb]

I wouldn't call it a fear of changing, but do think of it as an unnecessary change.
6 volts works great and saves money from doing the change.

Around here there is only one place, that sells only one six volt battery. It costs about twice what a 12 volt battery costs. The difference in cost easily covers the cost of the few bits needed to change to 12 volts. Being 12 volts allows me to use a $40 alternator instead of a $150 -$200 one, a high energy electronic ignition, standard LED replacement bulbs (about $30 for all the bulbs in about 3 cars sans headlights) as well as a modern stereo, cruise control, fuel injection etc. Not to mention 12 volt parts, can be had at every parts store across the country without a special order and waiting days or weeks for them.

[Hallabutt]

Around here there is only one place, that sells only one six volt battery. It costs about twice what a 12 volt battery costs. The difference in cost easily covers the cost of the few bits needed to change to 12 volts. Being 12 volts allows me to use a $40 alternator instead of a $150 -$200 one, a high energy electronic ignition, standard LED replacement bulbs (about $30 for all the bulbs in about 3 cars sans headlights) as well as a modern stereo, cruise control, fuel injection etc. Not to mention 12 volt parts, can be had at every parts store across the country without a special order and waiting days or weeks for them.

I find that comical. I have enough saved 6V parts to last two lifetimes, for my post-war cars! I usually get my 6V Optima batteries at swap meets, or through Amazon, but since they last more then ten years, I don't need too many. Of course I don't have all the modern conveniences either.

[TWChamp]

I agree with Hallabutt. I paid $25 for an almost new 6 volt battery at a swap meet to replace the 13 year old battery in my 1950 Champion.

If I was going far from home and had a weak battery, I'd replace it before the trip.