[Charlie Jones]

Rusty,
Before you dive headlong into a 12 volt conversion you might want to consider the following points.

Alternator brackets will have to be fabicated and you will have to locate a wide pulley to fit your 3/4 in. fanbelt.

Six volt starters will work on 12 volts,but, it will shorten it's life drastically. Especially if it's kind of tired already.

Unless you are an expert on both alternator and generator charging systems, coming up with a workable wiring circuit will be very difficult.

Six volt systems can be extremely reliable if they are properly Restored and maintained. They are capable of starting vehicles at 30 below zero if they are in good condition and in fact did so for many years before 12 volt systems came along.

Accessories such as radios and heater fans will not work on 12 volts unless the proper voltage dropping resistors are used.

Instead of converting to 12 volts I would suggest that you restore the original system properly. Make sure to consider the following:

Battery: Be sure to use a new "long tom" battery. They aren't hard to find, especially in the farm belt because John Deere (God bless 'em) used them for many years. Look at farm supply stores or implement dealers. John Deere also used Delco-Remy charging and starting systems and may be a source for many small parts such as brushes, bushings, and bearings for starters and generators. Implement dealers will probably have mechanics with experience with generator/regulator systems.

Battery cables; The bigger the better. With half the volts you must have twice the amperage to do the same job. The main mistake many hobbyists do with 6 volt systems is to use the skinny 12 volt style cables. Use the original type braided ground strap and at least a 2/0 battery to starter cable. Make sure there is a good ground strap between the body and the engine.

Generator and starter; Have both of them reconditioned. If you want to do this yourself start by disassembling and thourghly cleaning them. Check the field coils for continuity and shorts to ground. Take the armatures to an electrical shop or implement dealer and have them tested on a "growler" and then have the commutator trued and undercut. Reassemble using new brushes, bearings, bushings, and solenoid contacts.

Wiring; Check the wiring harnesses carefully for brittleness and deterioration. Fortunately, on your model car the wiring harness is divided at the firewall.The underhood wiring, which is most subject to deterioration, is replaceable seperately.

Tools; To work on any electrical system you need at least two things, a volt/ohm meter and a wiring diagram. A factory service manual is even better.

Good luck on your project. I truely envy you for finding such a gem of an old Pontiac. I hope you enjoy driving it for many years.

[stevep]

I agree with Charlie on the 6 volt system. All my straight 8's stayed 6 volt. If everything is good, you should be fine. Look for a 3EH battery, it has more cranking amp.

The only thing that I did was to put a 6 volt alternator in it. We had to make some brackets and it wasn't a bad installation. It worked great.

[Rusty]

Charlie and Steve,

I will definately take your advice into consideration. I have a few local shops that specialize in restoring generators for these old cars, so that wouldn't be too much of an issue. I did take it apart and clean it out last year and it immediately worked better.

That said, I also have a wiring genius that I'm good friends with who will be helping me with the application if I do it. He also happens to work at a place where I can get any part I needed fabricated (brackets, etc.)

I definately don't want to go through another unreliable summer as I did last year, so one way or the other, the car is getting fixed. I'll have to weigh everything before I decide a final direction, but at this point I'm still leaning towards the 12 volt and possibly a ron francis wiring harness. Have heard some great things about them.

Rusty

[Jack Gifford]

As I said on page 1, I agree with Steve and Charlie that six volt systems can work fine. Specifically, what "unreliability" did you experience that you attribute to the six volt system?

[stevep]

The only thing that I wold call unreliable, is the voltage regulator, which failed after 8 years. For what a good regulator would have cost, I had my local alternator shop give me a 6 volt alternator with an internal regulator and I never had another issue. We spent two hours fitting it.

[Bill Eveland]

Steve, do you remember the application for the 6V alternator? And did the wide belt generator pully swap over or what pulley did you use? Thanks

[Rusty]

There were various different unreliabilities that popped up, sometime intermittently.

The biggest issue was with starting. It would start fine a 2-3 times in a 2 hour period, but once you went over that point, it didn't want to start. Seemed like it was cranking fine, but a little extra spark/juice IMHO would've popped it off. As I said before the brushes on the generator were originally full of surface rust, but I cleaned those up with some fine sandpaper and since then the generator seemed to work the way it was intended. Talking to the local generator shop guy, he said that at their peek output they are only kicking out just enough to keep the 6v battery stable, say somewhere around 6.2v. I also talked to him about the starter issue if changing it over to a 12v and he said that the damage done/life expectancy lost would be virtually unnoticable. One of the other things I noticed late in the year when cranking the car was that the battery cable going to the starter was very hot and the plastic coating was melting at the very base. I checked all of the connections/grounds, and they were solid.

I also had issues with running lights, specifically in the tail section. My brake lights worked intermittently, as did my turn signals, and the two white lights didn't work at all. I tried changing bulbs as well as fixing the grounds to the lights which are basically grounded by the housing. Fixing the grounds seemed to help some, but not enough for the reliability I am after. I would think everything was fine and fixed, I'd end up driving home, only to get home and find out that I didn't have any taillights the whole way. Then the next day, the lights would be working properly, without having done anything different.

The radio in the car doesn't even work, but according the previous owner it had been working. So 1) either something happened to the radio internally or 2) something happened somewhere in the wiring to the radio. I've looked around under the dash and haven't found any loose/broken wires.

I also had some issues with some fuses at the firewall and the wiring associated with them. We also had other various wiring issues. I.E. we were checking wires that should've been hot, but were not, for whatever reason, we couldn't figure out.

So now....to me, with all the different issues, when I look at the cost and time to track everything down and fix everything with 6v, I think I'm probably going to come out ahead in the time category fairly significantly if I just convert things over to 12v and run new wiring that I know isn't broken in some hidden location. I'm not afraid to part with a little cash to save a headache and to give me peace of mind that I'm not going to have to constantly limp something along.

With these issues and what I've said in mind, Which do you think is worth pursuing the 6v or 12v?

Thanks,
Rusty

P.S. - I did call Generator Specialty here in St. Paul, and he gave me some other things to try first, much like you all have. I'm going to probably hold off on doing anything until mid-late March, since this weekend it's supposed to be -45 windchills here and I don't have the nice heated garage just yet But I will keep you updated on my progress, and most certainly will be bouncing things off of all of you. Thanks again for your help.

[Bill Hanlon]

Originally Posted by Rusty

One of the other things I noticed late in the year when cranking the car was that the battery cable going to the starter was very hot and the plastic coating was melting at the very base. I checked all of the connections/grounds, and they were solid.

Either the cable is undersized or the wire under the insulation is eaten up with corrosion.

[Rusty]

Originally Posted by Bill Hanlon

Either the cable is undersized or the wire under the insulation is eaten up with corrosion.

Bill,

I think that you are right about the cable. I think it's just a 12 volt and it should be a 6 volt. The generator guy guessed this as well and said that using a 12v cable on a 6v system is like trying to run water with a kink in the hose. I'll know a little more as I dig into this and rule certain things out, but if it's as simple as changing the points and a battery cable, that would be pretty nice

Rusty

[stevep]

Originally Posted by Bill Eveland

Steve, do you remember the application for the 6V alternator? And did the wide belt generator pully swap over or what pulley did you use? Thanks

Bill,

I called my alternator/starter rebuilder and he came up with one. He may have custom made it. We did use the wide pulley. I think that he had to special order it. We had to shave quite a bit off the mounting area to get it it fit and I think that we used a 65-66 big Pontiac upper alternator bracket as the new upper bracket. It also needed a little tweaking. If you have a good rebulder in your area, he should be able to get you one. If not, I should be able to help you.
BTW, it is a 1 wire alternator with an internal regulator. You will not be sorry!

[stevep]

Rusty,
You may need a wiring harness, actually, you probably do need one.

Now for the radio. If you have the service manual, it gives a decent radio trouble shooting guide. But 1st, do you have power going to it? If so, when you turn it on, does it hum? If not, you may need a viabrator. The other common fault with these radios is the OZ4 tube. You can change them with the radio in the car. Just take the 4 screws of the back of the radio and remove the cover. It will have a diagram in it. If you call 800 WE FIX AM, they will have what you need.
You will spend MUCH more converting to 12 volts. Remember, every light bulb has to go!

[Pontirag]

six volt systems are entirely suitable. Its not at all difficult to convert to a 12 volt alternator. it takes some thought but little efort. Regardless of which path you choose look closely at the condition of your wireing harness. that fabric insulation can be deceptive in its condition. When i converted mine to 12 volts I made my own harness much cheaper and of much better quality that anything offered commercialy. Essentially it was a copy of the origional harness with modifications for the alternator and additions such as spot lites. Cost was less than 300 dollars and too about forty hours. read a few books on it as well. Its no mystery at all, just well thought out effort.

[53texponcho]

Originally Posted by Rusty

Bill,

That's a good point. I'm leaning toward doing just some bolt on items for fun/interest, such as a dual carb intake (possibly) if I can find one and maybe just making a header. I guess I'm not overly worried about the performance aspect of the car, because like I said, I don't think it's ever going to really move out. I'm really just interested in the reliability factor with it. Starting soon, I hope to start digging into the starting issues I was having with it in the fall, and possibly rewiring it to a 12 volt system.

It's a pretty neat car that I think I was pretty lucky to come across for $5200. It has every chrome option that I can find for the car, so I guess I'd really like to just dress up the motor compartment a little bit.

I'm also really interested in trying to adapt power steering onto the straight 8 if anyone has any experience with that, or knows anyone whom might know, let me know. I want my wife to be able to drive this as easily as I can, but with the "strongarm" steering in it now, I don't think she'd feel comfortable driving it.

If you can't find a high compression head 7.7 compression you could have your head milled. I have a 53 and my problem was my engine was shot so I opted to go with a 55 Pontiac V8. It has been a struggle getting the correct parts but for double the horsepower I hope it's worth it. I am converting to 12 volt and you will need to get the good heavy duty voltage reducers for your radio and do some rewireing for the alternator. Your car looks good now so I stay with the straight 8 and just go throught the engine. Good luck and let us all know how it turns out.

[Rusty]

Well I kind of have everything worked out. The 1/0 battery cable made a HUGE impact on the starting/reliability. The amp meter is even showing that the generating is managing to sufficiently charge the battery. I'm also completely reconsidering what I want to do with the car. I originally thought about making it a copper-orange on the bottom with a white pearl (cadillac) on the top, but after messing around on photoshop with it, I think I still prefer the original look. Now I'm think I should just throw an interior in the thing and be done with it until I completely rebuild the car a few years down the road. Just thought I'd update people on what happened with the car. Thanks for everyone's help.

Someone somewhere mentioned that they had adapted a regular radio into their car while keeping the original 6v system. If you read this can you give me some info on how to do this. Or if anyone else has an idea on how to do this, I'd be very appreciative.

Thanks,
Rusty

[stevep]

My friend put a later radio in his 52. He has a 12 volt battery in the trunk and charges it when it needs to be charged, which is not that often. He tests it with a load tester the day before he goes on a trip.

[Jack Gifford]

Originally Posted by pontiac jack

... To power FM/Cassette, I put an old 12V battery in the trunk, with a cheap DC-to-DC converter to keep it charged.

Maybe it was this post by me that you remember? DC-to-DC converters are available in many flavors from Antique Electronic Supply in Tempe, AZ (800-706-6789). The 6V-Pos.Gnd-to-12V-Neg.Gnd version that I used in my Plymouth cost less than $20. I powered it from an IGN terminal of the Plymouth's ignition switch, so the 12V battery in the trunk is being charged whenever the engine is running- no need to open the trunk- just forget about it. Almost any 12V battery which is at the end of its useful life- i.e., won't reliably start a vehicle- will still work fine for a radio, tape player, etc., so the battery is virtually free.
I'm glad you're keeping the car pretty much original, and that you're getting satisfaction from the 6V system (gee... sure is hard to resist saying "I told you so"!).

[Rusty]

Jack,

Thanks for the tips. It is hard to say "I told you so" but I'm sure you could give it a shot anyway Since I asked this question I also was pointed in the direction of a voltage booster that you can buy for around $100. It's basically a box that you mount under the dash that will allow you to change the 6v current to 12v in order to utilize the power for modern radio, cb, or various charging devices of cell phone, etc. I might see if I can find a deal on one of those, as it would be nice to not have to worry about another battery and running wires from the trunk. But thanks for the info, I will definately take it under advisement.

Rusty

[Pontirag]

If your just cruising around at low speed your generator will not charge. or it will under charge. people who know will agree that generators begin charging at a higher rpm than alternators. People mess with the regulator thinking its at fault and mes it up too. Dont be afraid to Take it out and run it at sustained moderat reasonable speeds to get it up and charging. Clean all the contact points in the regulator befor you go in and tweak stuff. Service it according to the manual befor you condem any component. POST 1001!

[Rusty]

Pontirag,

Thanks for the caution, but I don't think the voltage booster I'm looking at gets involved with the generator at all. I believe from what little I've read about them that it basically branches off of some other wiring and somehow within the small box unit converts the 6v power into power usable for your standard 12v radio, etc. I'm going to be doing some more research and calling on the thing before I go that route, because right now it sounds too easy to be true I'll let people know what I come up with in case anyone else is in the same boat as me.

Rusty

[Jack Gifford]

Rusty- the "voltage boosters" you're talking about are known in the industry as DC-to-DC converters, such as I bought from Antique Electronic Supply. To buy one with enough output current capacity to directly run a sound system would be very expensive. A "junk" 12v battery serves as a perfect "buffer" (capable of many, many amperes and is basically "free"), so the converter only needs to supply the average current consumed and can be inexpensive. Have fun!