6v to 12v step up converter

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Bobacuda

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Off the wall question, but I have not been able to find an answer on the Pilothouse forum or The hAMB.

My 53 Dodge truck is mostly original. 6 volt positive ground. The 70 yr old aftermarket heater core is totally shot - rad shop can’t fix, and no aftermarket cores are close to the same.

Online, I can find new aftermarket heaters, but they are 12v negative, with most drawing 8-10 amps.

I can find “step up” converters to raise the 6v to 12v, but their instructions don’t discuss polarity. In addition, some max out at 4 amps.

1. Anyone here have experience with step up converters, and if so, what about polarity issues?
2. Small DC fan motors have fixed magnetic fields. Won’t connecting hot wire to negative nd ground wire to positive spin the motor backwards?
3. Will the 12v fan motor work on 6v, just slower
4. What is the impact of running an 8 amp draw on 4 amp max?

I am considering purchasing a heater and a 6-12v step up converter and experimenting, but I would prefer to have educated and experienced input to guide me.

Thanks in advance.
 
Have you tried AMS Obsolete? I refuse to believe no one has one. Somebody out there does.
 
RustyRatRod said:
Have you tried AMS Obsolete? I refuse to believe no one has one. Somebody out there does.
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I have been all over the web and various sites without a replacement. Tbe rad shop specializes in old cars,he has not found anything either.

The problems are where the water tubes are located, and they are shaped, threaded pipe threaded into the core also is threaded so that large nuts attach the heater to the firewall
IMG_1571.jpeg


Thanks for the lead. I think I have checked it, but I wii go there.
IMG_1570.jpeg
 
Bobacuda said:
I have been all over the web and various sites without a replacement. Tbe rad shop specializes in old cars,he has not found anything either.

The problems are where the water tubes are located, and they are shaped, threaded pipe threaded into the core also is threaded so that large nuts attach the heater to the firewallView attachment 1716350783

Thanks for the lead. I think I have checked it, but I wii go there. View attachment 1716350782
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No problem. If anybody has one, it will be them. And if not, you may also try vintagepowerwagons.com
 
I'm sure, SOMEWHERE there is or was 6V inverters to 12V. There used to be such accessories available for 2 way radio installations, esp in such as snow plows and fire trucks, etc.

OLDER small motors are not permanent magnet fields. Older small motors, even such as used in our A bodies, are all electro magnetic, or wire would fields. These motors do not care about polarity. Such is true of the older cars on starters, or any small motor in the car

You might try to find an older 12V motor to swap in. An inverter is likely to be expensive.

Yes!!! Newer PM (permanent magnet) field motors WILL revers if you reverse the lead wires.

Also keep in mind that your 6V generator is likely VERY much limited
 
I Feel your pain. I have a 53Plymouth 6v positive ground vehicle as well and I went through this trying to get a 12 volt aftermarket radio to work. Had to go to an anodized aluminum bodied casing for the inverter I got from JC Whitney. I would think that any inverter you use for something that draws as many amps as an electric heater will surely kill your six volt battery. I would retrofit a different core and replace the motor (if bad) with another six volt motor. You can isolate the mount of the motor to reverse the polarity if need be.
 
Bobacuda said:
I have been all over the web and various sites without a replacement. Tbe rad shop specializes in old cars,he has not found anything either.

The problems are where the water tubes are located, and they are shaped, threaded pipe threaded into the core also is threaded so that large nuts attach the heater to the firewallView attachment 1716350783

Thanks for the lead. I think I have checked it, but I wii go there. View attachment 1716350782
Click to expand...
Contact Bob at Glen Ray Radiators. He will need some dimensions but I bet he can re-core that.
 
Nothing on AMS.

Talked to the rad shop about 30 minutes ago. One of his core suppliers is willing to try a rebuild- estimated $360, plus cost of failed cores, plus shipping, plus taxes…. I will freeze before I have a $500 heater as seldom as I will use it. I am cheap. If I cannot figure out a solution, I will order the new heater and step up.

Any comments on 4 amp power to 8 amp motor?

On the bright side, if the 12v solution doesn’t work for me,I will save it for the 51 Dodge farm truck I am starting to rebuild - it wii have 12v neg ground electronics.
 
Oh, and I will try it on 6v first, withe the heater’s + wire connected to the trucks - (hot) wire. No other mods. It can spin slow, no problem with that.
 
I would convert the thing to 12 volt and be done. That's just me.
 
Mike69cuda said:
Can you convert the car to 12v? Might save a lot of headaches on down the road.
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Best option...Lights that actually work, starter that cranks instead of laboring... They build alternators that look like generators if looking stock is important... Distributor won't care....

FWIW an 8 amp 12v draw being fed 6v is actually gonna use 16 amps.... Which probably exceeds the output of your generator...

BTW that relationship between amps/volts is also why the starter will work so much better... Most starters draw 100-140 amps at 12v... Which means it draws 200-280 amps at 6v....
 
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I would as well. And for a 6V source, use an alternator that is "Y" or star would stator. the "Y" center connection can be brought out and used for smaller amperage accessories on 6V such as gauges.

You don't need to convert the starter, unless one is available. If it uses a starter solenoid, for sure buy a 12V one

You don't need to convert stuff like electric wiper motors, just use one of the "step down" resistors. You must follow the directions in them for amperage

Change the coil to either a 12V coil or one such as used on the cars we discuss here, that uses a companion ballast.
For certain, convert to NEG ground. You will have to reverse the ammeter.

Don't try to use a 6V radio

There used to be simple little devices made especially for gauges to reduce them to 6V I don't remember the name off hand.

Obviously, change all light bulbs

Generator. Either convert to a 12V generator and matching regulator, but much better, of course to use a 12V alternator. Some guys have used 6V generators on 12 by getting a similar 12V regulator, and likely reflashing the generator. You must figure out what type of field wiring you have. I can never remember which is "A" and which is "B" One has the field grounded, and the VR sends it power to cause charge. The other has one end of the field hooked to the armature (output) and the VR grounds the other end of the field winding.

Generator VR's must not be for more amperage than the generator is rated for, and generally must be for the proper ground. Many can be "either" ground polarity. There actually were a few rigs made with 12V pos ground.

Some guys used 2 6V batts in series, or "tapped" a 12V battery to give 6V for some components. I recommend against that. This unbalances the battery and it will never be quite right
 
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