12volts for starting;6volts for running

[GeorgeLeonard]

Can anyone advise me on this? I saw it on ebay and it looks interesting but Im just not sure my $7.50 would be well spent. The seller uses two six volt batteries that are hooked to supply his car with twelve volts for starting and then immediately return to 6 volts once the car is started. Neat trick if you can do it. But if its such a good idea, why isnt everyone doing it?

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&rd=1&item=380094502215&ih=025&sspagename=STRK%3AMEWA%3AIT&viewitem=

[Johnny S]

He had the same thing listed for $5.00 just a week ago! Inflation?

[Johnny S]

I asked if he had photos of the installation that he describes and the answer was no. I found that a little odd.

The concept works however. If you could get everything (or most everything) stuffed into a look-a-like battery case (e.g. 2 - 6 volt Optima's) it probably would work pretty ok. Otherwise it would probably look pretty cobbled up.

[TodFitch]

If you want 12v for modern accessories, then convert to 12v.

If it is not starting easily on the original 6v then there are repairs needed to the system and starting on 12v is just a band-aid to hide that fact. Fix the problems and you won't need a 12v starter kludge.

At least that is my story and I'm sticking to it.

[Plymouthy Adams]

if he gave you the schematic he would have nothing to sell... as you still need do is buy the relay and the other battery and cable...

P.S. check out some of the tractor sites...!!!!!!!!!1

[Norm's Coupe]

You can have a system like that. I believe there was a discussion about this a very long time ago here on the forum. Should be in the archives if you have them.

That said, I've never seen a reason to do something like this. A 6 volt system with good wiring and properly tuned should start right up anyway. Of course it will crank slower than 12 volts do, but the car will start just fine as is with the 6 volt only.

[randroid]

Gents,

All 12v vehicles with points (and many with EI) run the engines on 6v and always have. When 12v systems were introduced they were flaunted as easier starting and having brighter lights but those reasons have been all but dismissed on this forum. What 12v did was to greatly cheapen the price of wiring the cars because smaller gauge wire could be used, and when you're talking thousands of cars per month (or more) those savings became substantial. The points, on the other hand, became toast rapidly with 12v running through them so a coil of resistance wire was wound inside a porcelain block (usually mounted on the firewall to keep the heat generated from them from starting fires) which allowed 12v when cold to get a poorly tuned car started fast, then quickly resisted the flow down to 6v.

My brother's '76 Dodge truck went through them so fast he kept a spare or two in the glove box with a screwdriver to change them when the truck suddenly quit running. Cheaper than paying a mechanic to find the problem, I guess.

-Randy

[Plymouthy Adams]

Chrysler was know to have placed a few of these resisitor in places where they can easily be hit by rain especially when the hood was opened (long sunken hood on the 76 Dodge both side of center line) thus snapping the resistor wire when rapidily cooled...relocation or shieling of the resistor would have saved some money.

[Norm's Coupe]

I remember those resistors too. Had a 78 Aspen and 80 Volare at the same time. Wife got stranded once in her Aspen. Always carried a spare in each glove box after that. They only cost a couple of bucks back then. Even used one to rescue some stranger late at night in a parking lot. They were on the firewall back then. In an emergency with no tools, just unplug the old one and plug in the new one and let it hang until you got home. Was held onto the firewall with one bolt.

[Powerhouse]

how would that work with the generator or volt regulator. Wouldn't it need twice as many, one for each battery?

[norrism1]

If I remember correctly, the 1960's VW Bug used 2 6v batteries under the back seat.

[martybose]

how would that work with the generator or volt regulator. Wouldn't it need twice as many, one for each battery?

Nah, you just use a solenoid that puts the batteries in parallel until you hit the starter button, then it switches the leads so they are in series to produce 12 volts. It would charge on 6 volts.

I had a setup like this back in the late 60's in a 6V Volvo that had a later motor in it with a 12V starter. The solenoid was built into the battery itself.

Marty