Switch to 12v

david moore · #1 02-12-07, 17:21

Now that I have got my Ford F8 engine running, I find it so much easier to start with 12v help. I have a 12v coil so I may switch over. None of the other wiring is installed yet - I am just jury-rigged for the battery/starter/coil. If I do change over to 12v, obviously the voltage regulator has to be changed - and the bulbs of course. And the various senders? But what about the generator? I am a novice re electrics so assume that the gen will have to be changed? Is there such a thing as a 12v generator fior a Ford CMP?

PPS · #2 02-12-07, 17:42

I just know that this is going to earn me the

or at least a

from the CMP addicts, but here goes

I take it that the electrical system is 6 volt??

If so, the generator will have to be changed/modified to a 12v machine. The starter would also need to be changed/modified as it will eventually burn out if it is a 6 volt.

I will

and

those of greater knowledge than I in matters CMP (Ford or otherwise)

Paul.

Barry Churcher · #3 02-12-07, 17:55

Hi David
There are companies that will convert your generator to 12V but it can be pricey. There are also 12V alternator kits to mount a Chev alternator in the stock generator position. The downside of the alternator is that it is visible on a Ford when you open the hood. The upside is that it is trouble free. For your purposes which I know are being able to drive your vehicle anyplace, anytime, I would opt for the alternator. You need minimal wiring also. The starter doesn't care if it's run on 12V as long as you don't crank it over forever. The horn also is the same. You will need a voltage reducer for the fuel gauge also.

On the other hand a good working 6V system with a good battery should start without difficulties.

Cheers,
Barry

Geoff Winnington-Ball (RIP) · #4 02-12-07, 18:37

Quote:

Originally posted by Barry Churcher
On the other hand a good working 6V system with a good battery should start without difficulties.

Barry, you forgot the caveat -- "except on Fords, where nothing works but animal sacrifices in conjunction with certain ritualised chants in the key of G and due notice to the relative positions of the stars at precisely 1035 GMT on even days of the week"...

Barry Churcher · #5 02-12-07, 19:16

Geoff, I will apologize to the whole forum for my misinformation. I find no shame in admitting when I am wrong.

To clarify my earlier post, there is substitute for caliber in guns, cubic inches in cars and amperage/voltage in a Ford. Being a Chevy man it is easy to forget the trials of being a Ford owner. Your statement is very well put:

"except on Fords, where nothing works but animal sacrifices in conjunction with certain ritualised chants in the key of G and due notice to the relative positions of the stars at precisely 1035 GMT on even days of the week"...

I very well remember hiding a 12V battery in an ammo box in the back of my carrier for those frequent occasions when the Ford Syndrome set in. Has anyone successfully started a hot Ford with a crank?

Cheers,
Barry

Mike Timoshyk · #6 02-12-07, 19:30

Do you mean that once a month crank or the bent steel one....

Geoff Winnington-Ball (RIP) · #7 02-12-07, 19:41

Quote:

Originally posted by Mike Timoshyk
Do you mean that once a month crank or the bent steel one....

david moore · #8 02-12-07, 19:42

Hey guys - even Chev could be dumb - what about the bearings/lube arrangent in the original Chev CMP 216 engines! But I do have to admit that my Ford does have its frustrations - the main being try to get at the distributor without removing the radiator!

Thanks for the comments Barry - I presume that the oil sender and the temperature sender, being electric, would need voltage reducers too?

I may just opt to do what most seem to do -- live with 6v but have that 12v battery tucked away for the start. My engine will start first go with 12v but needs quite a few attempts with 6v. I feel, from using the hand crank, that the engine is fairly tight - I hope from a fairly recent rebore before it was set aside. A tag shows that it was rebored.

Just to be controversial - I have owned and run a Chev CMP, a Ford CMP and a Dodge half ton. By far and away the easiest to work on and comfortable to drive was the Dodge - dare I also say reliable! And thats the one that had the least government/military involvement in design specs etc.!

Having said that, the Ford 8cwt CMP is by far the cutest!

Has anyone out there actually done the 6 to 12 switch on a Ford?

Geoff Winnington-Ball (RIP) · #9 02-12-07, 19:46

Quote:

Originally posted by david moore
Has anyone out there actually done the 6 to 12 switch on a Ford?

Numerous of the lads here, IIRC... one of the lads will pipe up eventually!

mike mckinley · #10 02-12-07, 20:19

hi david

one of my jeeps came stock with 6v electrics. the previous owner changed it over to 12v. the changes were, 12 alternator, solenoid, coil, lightbulbs. he retained the stock 6v starter, which is still going strong after20+ years. i guess when you consider the limited ammount of time a starter is used it likely won't burn out too fast. then again, we're talking about a ford here, and due to the erratic engine anomilies, the starter may get much more use than say a fine general motor's product.....just joking

mike

Max Hedges · #11 02-12-07, 23:17

the only problem we had was the spark was to good for the dist cap so we put a resister to drop the power to the coil to 8 volts
and used little thing that Ian sent me to drop the dash gauges to 6 volt
and used a 12 volt generator
starter ok
this is the FORD that Jiff drove with a BIG grin
right old boy
Max

cletrac (RIP) · #12 02-12-07, 23:48

Why don't you just get an 8 volt battery and bolt it in? Everything works and the starter spins a little faster.
8 volt battery

Geoff Winnington-Ball (RIP) · #13 03-12-07, 01:00

Quote:

Originally posted by Max Hedges
this is the FORD that Jiff drove with a BIG grin
right old boy
Max

Works like a charm, Max! I almost drove it home with me, 'cept I figgered you'd probably stuff it with snakes and spiders while I wasn't looking!

Ken Hughes · #14 03-12-07, 07:41

hey Jiff ,if you can,t afford a Ford dodge a Dodge!
David if you stick to 6v make sure you have extra earths running everywhere,because over 60+ yrs things get painted,rusty and dirty and they don,t work like they did when new,my Ford now starts like a 12v system!!thanks to Alex Blair i think.
If you go 12v you could source a gen/starter etc out of a Ford Thames Trader v8 and put the 6v reducer on the gages

david moore · #15 03-12-07, 13:54

The 8v marine battery sounds like a great idea - anyone tried these? Are they availabale in Canada?

chris vickery · #16 03-12-07, 15:04

David, when I sold my HUP, the fellow who bought it wanted it to be trouble free (12v) and had me do the conversion.

Don't fall into the trap of everyone telling you that the generator needs to be converted to 12v. It will work just fine as a 6v unit on 12v for many years as long as you don't crank it over for extended periods of time. 12v on a 6v starter should fire your vehicle in seconds.

As for the generator you can buy one out of the US that fits in place of the original one that is actually an alternator that uses the original style ford mounting and is a single wire hookup and internally regulated. A frined of mine has this setup on his 1937 coupe. As for a chev, one can easily mount a standard alternator with original bracketry from a 235cid motoras this is what I did on the HUP

All the bulbs is a simple one, just exchange for 12v.

Yes, the sending units on the fuel tanks present a problem as does the fact that your guages all run on 6v. You can either forget about using them, mount some postwar 12v ones in a discreet location or use a 6/12v stepdown unit.

There is no really simple way but all of my suggestions do work from my own experience.

There is another option, albeit more complex requiring a wiring diagram which I have also done before. This involves utilizing 2 x 6v batteries. The advantage of this setup is that you would run all your systems on 6v and use 2 x 6v in series for a 12v starting system after which time all is regular 6v. I would not neccessarily reccomend this unless you are quite adept with electricals as it can still provide you with the typical 6v headaches.

NOW, for my question...
Why would you really want to do a 12v conversion? The original 6v will work perfectly if you have met the following criteria;<<

-New, 6v battery, exercised on a regular basis and kept on a 1a trickle charger when not in use
-rebuilt generator, starter and new voltage regulator
- new wiring
- sqeeky clean and tight grounds
- new coil, plugs and sparkplug wires
-rebuilt and tuned carb and properly tuned engine
-rebuilt and properly timed distributor ( don't use the manual, you need a timing fixture)

hope this helps, Chris

Mike Timoshyk · #17 03-12-07, 15:36

all this talk of conversion from 6 to 12v....is the requirement necessary because of old wiring and components that have not been refurbished? If in fact the darling Ford has a penchant for being unreliable with 6v system I may have to re-think before I get into the re-wiring.

I have had the major electrical bits professionally refurbished to allow for (hopefully) trouble free operation.

Any more advice.

cheers

Mike from Windsor

Geoff Winnington-Ball (RIP) · #18 03-12-07, 15:39

Buy a Chev?

Mike Timoshyk · #19 03-12-07, 18:26

From the sounds of it I have joined the SMFS (Sado Masochistic Ford Society)

Mike

Geoff Winnington-Ball (RIP) · #20 03-12-07, 19:02

Quote:

Originally posted by Mike Timoshyk
From the sounds of it I have joined the SMFS (Sado Masochistic Ford Society)

Mike

Not quite, Myke... you've been elevated to the Sado Masochistic (Under Restoration) Ford Society...... yes, you're now a - wait for it... S.M.U.R.F.!

(god, I crack myself up sometimes...)

cletrac (RIP) · #21 03-12-07, 22:57

Most older 6 volt systems spin the starter slower than 12 volt systems. The starter bushings get worn and the armature starts dragging on the fields and this really slows things down. Add to this that the motor's compression gets down a bit so the motor needs to spin faster to start. Then add in the Ford factor and things get real interesting when the motor's hot.
If you have a good starter and the cables and grounds are making good connections they'll usually start. Around here a lot of farmers with an old 6 volt truck put in one of those 8 volt batteries to spin the motor that little bit faster. A 6 volt generator usually charges 8 or 9 volts anyway so you don't create any problems. The odd time you have to crank up the voltage by adjusting the regulator to get it to charge 9 volts but that's it. Most battery companies make an 8 volt battery.

chris vickery · #22 04-12-07, 00:06

I have had the major electrical bits professionally refurbished to allow for (hopefully) trouble free operation.

My point exactly Mike. A properly restored vehicle is one whereby an individual has totally gone over everything; mechanical, body, mechanicals etc.

CMPs were designed with 6v electrical systems, the technology of the day. There is absolutely nothing wrong with a properly done and maintained 6v setup...

david moore · #23 04-12-07, 01:57

Thanks for all the comments on this issue. The main point to me is something I knew all along from my jeep - check and improve the grounding! Given that I have new battery,coil, points, distributor cap, condenser,rotor, wiring - I think thats where my problem is. Will keep you posted.

Barry Churcher · #24 04-12-07, 02:20

We currently have a HUP at the garage for a little refurbish. One of the first things we did was new battery cables. This vehicle had replacement cables that were designed for 12V. Changing to the heavier cables (pricey) paid off and the old 216 cranks over like a bandit.
Barry

Bob Moseley (RIP) · #25 04-12-07, 09:26

Hi all
Barry has hit the nail on the head. Don't use modern wiring for 6v. It requires the old thicker wire and the older heavier battery cables. Then ensure you have good earths everywhere. If you are going to restore a vehicle properly leave everything as it was and enjoy the pleasures/frustrations of driving 65 year old vehicles.
Bob - Restoration Purist.

Geoff Winnington-Ball (RIP) · #26 04-12-07, 12:23

Quote:

Originally posted by Bob Moseley
Hi all
Barry has hit the nail on the head. Don't use modern wiring for 6v. It requires the old thicker wire and the older heavier battery cables. Then ensure you have good earths everywhere. If you are going to restore a vehicle properly leave everything as it was and enjoy the pleasures/frustrations of driving 65 year old vehicles.
Bob - Restoration Purist.

Bob, you bring up a good point. For the benefit of those who may not have access to the 'older, thicker wire', have you or anyone else done a rough comparison of suggested wire gauges for the various applications on any given vehicle? That might be useful to some here trying to bring their old girls alive again (trucks I mean, not wives

).

chris vickery · #27 04-12-07, 16:43

In layman's terms, as one decreases the voltage, the amperage increases=more heat.

On a cmp one will find mostly 14g wire with 12 g and 10 g wire where required.

On modern vehicles, most of the wiring is 18 g or lighter as 12v requires only lighter wire to carry the amps.

You may find that the battery cable size on modern vehicles to be about a 6 gauge while the older 6v is around a 2 or 3 gauge.

Ever notice if you go to purchase a set of battery boosting cables that the higher end ones are quite expensive and a heavier quality? That is because the heavier cables carry more "juice" than their lighter ones.

For the technically inclined, amps= watts / volts

Ken Hughes · #28 07-12-07, 19:31

Hi guys, we are currently rewiring my ford and have sourced the correct gauge wiring for 6v.
Wiring and fittings cost around $2oo nz, and am fitting a modern fuse box for safety.

Rob Fast · #29 16-12-07, 00:43

It is our experience after converting from 6 to a 12 volt system that the 6 volt bulbs with a thicker filament last longer. Cheers Rob

Alex Blair (RIP) · #30 16-12-07, 01:02

Quote:

Originally posted by chris vickery
In layman's terms, as one decreases the voltage, the amperage increases=more heat.

On a cmp one will find mostly 14g wire with 12 g and 10 g wire where required.

On modern vehicles, most of the wiring is 18 g or lighter as 12v requires only lighter wire to carry the amps.

You may find that the battery cable size on modern vehicles to be about a 6 gauge while the older 6v is around a 2 or 3 gauge.

Ever notice if you go to purchase a set of battery boosting cables that the higher end ones are quite expensive and a heavier quality? That is because the heavier cables carry more "juice" than their lighter ones.

For the technically inclined, amps= watts / volts

What about R....???

Watts(POWER)
=E X I

I(Amperage)= E(Voltage)/(Over) R (Resistance)..

I always used welders stinger cable on wiring the heavy 6 or 12V stuff..It is very flexible and properly designed(Braided) to carry high amperage..