My 1937 ford has really nice stock dash gauges. I have never been successful in converting the 6 volt gauges to 12 volts. So maybe use two six volts and hook them up in series for the 12 volt starter on it's 430 Lincoln engine and starter. I'm going to mount the batteries in the trunk anyhow, so plenty of room. I don't want to take a chance on ruining the gauges.
You’ll need some type of isolator, but it would be more cost effective to used voltage reducers to the gauges, and just use a 12 volt battery
Which gauges exactly do you want on lower volts? The lights can just go to 12v bulbs. For the gas gauge maybe use a reducer. You should not use a amp meter anymore. for my conversion. I mainly change the bulbs. New gauge tools some the spots. I have a separate gas gauge. But the radio is the old 6 volt in a reducer. a bit confused sound like you have a New engine. Rewire for the new engine. If you have old wiring. for all the 6 volt guys. .. if you are having issues cranking. Use new thick battery cables go tot he online battery cable place and have them made. Size 00. Then get an 6 volt Optima. Worth the money. It will crank over like a new car. the site is batterycablesusa.com measure your cables have them made. Worth it.
C&G Ford parts have voltage reducers that are actually a copy of Ford parts. Sixty's era Fords had 6 volt gauges and a 12 volt system. I have them in my 48 sedan, and they work flawlessly.
I use a solid state reducer that you can daisy chain to the gauges that need it. You can get them on the auction site. Sent from my iPhone www.speedoservice.com Should I rush your rush job or the rush job I was rushing when you rushed in?
I wouldn't think an isolator is needed, just tap off of the first battery for 6v (have 48v carts at work that have 12v accessories). But yes, cheaper to go to 12v and runtz the gauges.
Daisy chained means different things to some people, the gauges have to have 6 volts run to them. So they need parallel drops, it you put all gauges in series, each load takes voltage.
Like the above post says you do not need an isolator just take the 6 volt supply off of one battery. I take it that you will be charge them at 12 volts. With the batteries in the boot you will need heavier duty cables for the starter and earth. over here we can get a single 12v battery with a 6 volt tapping as per picture. I have before on a battery with the exposed cell links drilled and tap into one for a 6 volt take off bit like the picture really.
What type of battery is that? I may be incorrect, but 2 6 volt batteries in series should be 12 volts measured at any point? What am I missing?
In reply to your questions Budget36. It made by a specialist company over here for people that want to covert old cars etc to 12v for starting and lighting but keep the 6v gauges etc. Most old batteries had the cells connected by a bar on top as per picture I posted earlier. Now a 6v battery is made up of three cells of about 2 volts each connected by a bar. So now if you look at my rough drawing you will see that if you connect a voltmeter from Batt 1 Positive terminal to bar A you will only get the voltage of the 1st cell. If you do the same between Positive and B you will get the combined voltage of cells 1 and 2 and so forth. Easy way for you to check this out is to get 2 off 12 volt batteries connect as per the 6 volt batteries in my drawing put a voltmeter between the 2 negatives terminal posts or the 2 positive terminal posts and see what voltage you get. Hope this helps
The electrical posts are always entertaining. Share some of your failures in converting the 6 volt gauges to be used in a 12 volt vehicle please. We can tell you what you did wrong if you give us some details. The solid state voltage reducers are by far the best solution. Cheap, easy and reliable. IF you choose to make the poor decision of using two 6 volt batteries in series, make sure you power the gauges from the battery that has the ground connected to it. Batteries in series need to be matched for size, and it's also a good idea to make sure you install/replace both batteries when it's time to do that, otherwise you'll have charging balance issues. Not to mention the space, weight and expense that two 6'ers will take/weigh/cost. Why not use an ammeter? Brainwashed by the "your car will burn to the ground" crowd? An ammeter, done correctly, works fine. Done correctly may mean you need to include a shunt to offload some of the current through the ammeter.
The problem with using an old ammeter is the rating. Most 30's cars have 30 amp amp meters at most, if you hook that up to an alternator putting out 60 to 100 amps you have a fire in the waiting. If you use a runtz voltage reducer for the 6 volt gauges and change the amp meter to a volt meter you will be fine.
Understood. Part of my posting says "done correctly" which in the case of a low current ammeter means using a shunt to offload some of the current that goes through the ammeter. I edited my post to add that bit of detail.
If you wire 2 6V batteries in a series, you just end up with 12 volts, correct? I'm not sure if that really would solve your problems. You could wire them parallel, so your gauges would still hook up to 6V, but then you're trying to spin the starter with 6 volts, just with more amps.
Say 2 6v batteries in series. First battery measuring from + to - is 6V, same with other battery (if measured on the same battery). Measuring + of 1 battery and - of the other is 12v. But to the op, I used the Runtz reducer on my '47 Ford (among others) and the NOS factory gauges work perfectly (one per electric gauge). Waaaay better option. https://fifthaveinternetgarage.blogspot.com/2015/11/the-runtz-story_10.html
That is really easy to do. I did similar on a high compression Lotus Cortina to start on 24v [2 x 12v in-series] and everything else was 12v [12v parallel] You need 2 x SPDT Relays "Reverse post [87A]" wired so they connect the 2 batteries parallel ["Neg to Neg" and "Pos to Pos" ] when not activated. And you also need a Ford starter relay [solenoid] to connect the batteries in series. So when all relays are activated the parallel circuit is disconnected and the In series circuit is connected. Now you can also add fusible links between the parallel relays to prevent a meltdown if there is a relay failure , but with clever wiring this is not needed. Both parallel relays are activated together by splicing posts 86 together to the starter button post 85 on the "Neg to Neg" relay is grounded with post 30 on the same relay. On the "Pos to Pos" relay post 85 is connected to post 87 of the "Neg to Neg" relay [if the Neg to Neg relay fails the Pos to Pos relay cannot switch over] Post 85 of the Pos relay gets grounded when the Neg relay diverts over Now on the "Pos to Pos" relay post 87 is connected to activate the Ford starter relay. [if this relay fails, the Ford starter relay remains open]
430 Lincoln? You are one of the few people I would recommend going to 12 volts. I would also suggest going to more modern gauges. "My pop sez yer gonna drive me to drinkin' if you keep on drivin' that Hot Rod Lincoln!"
I got that one. I took it and a new Ford Bronco type (Standard) regulator to the instrument shop to make sure the original fuel and temp gauges were working properly. Apart from the gauges, they said use the solid state reducer as it was constant and accurate. The new Standard regulator has a miniscule adjustment screw and had to be wound up from only 2.5 volts! It is now the spare.
The fuel tank gauge is the only gauge you’ll have to run a reducer. Get a good one. I burnt up two gauges on my 37 using cheaper reducers.
is the '37 gauge cluster about the same as the '39? if so, the temp gauge will not need anything, the amp gauge can be used without change also, so all you need to worry about is the fuel and oil pressure gauge. I made some voltage reducers from a voltage regulator chip IC, #7806 will give you 6 volt output, you can look up the wiring on the internet and the component is very cheap on e bay type places. Mine has been working for 7 or 8 years with no problem. Very easy to wire up, 3 terminals, one 12 volts in, one ground, the last one is your 6 volt output. they cost a couple of bucks each.
here is my dash gauges, 1938 ford. just the oil and fuel gauges need a resister of some kind, right. as a constant voltage regulator off a 1959 or so Ford dash?
You can source the regulator from a Ford or Dodge up to around the mid/ late ‘70s. Last I checked a new one through NAPA was around 30 dollars. But if you only need one, then aRuntz might be less expensive
I did just what you are doing back in 1967. But back then the 12 volt batteries had lead connectors exposed. I just tapped into the middle of the battery to power the car. And oddly enough it was on a 430 MEL also! I had the 12 volt starter and generator that came with the 58 Lincoln engine! It worked perfectly, on my six volt ‘55 Ford But I realized that I was also running my ignition on 6 volts! So I just wired in a separate toggle switch to power the ignition! The whole car was six volt, with the exception of the starter, generator and ignition. Bones
I think I will use a couple of the runt resistors . I called speedway in lincoln, said they could not confirm they are usa made. So I will buy them directly from the company. Looks like fairly easy to hookup. Thanks and happy new year. Stay safe
Way back in the soft top battery days when the straps between the cells were exposed or just covered with a bit of tar guys used to put a screw in the strap between the third and fourth cells of a 12V battery to tap off 6 volts to run a 6 V radio or accessory. That isn't doable now but two six volt batteries would accomplish the same thing.
Is there no companies in the States that do replica classic car batteries with the exposed straps. We can get them over here.
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