I just purchased a '49 Ford F-3 dump truck and am trying to get it started. The old battery would not take a charge so I bought a new one and now it turns over, but not fast enough to get it started and I do not want to keep cranking. I have been able to get it started by using a 12V jumper pack. Is this the reason people switch to a 12V system? Does it hurt anything using a 12V jumper pack just to get it started?

 

You may have to do some changing of the plug wires, and the works. Also check the ground...boy do these old ones need a solid ground. Don't know about the 12 volt starting question you pose though. jim
http://www.48f-1.com

 

Make sure you have good connections at the coil, dist.,Etc.... and take the starter out and clean all the mating surfaces. They need to be real clean. Also take a piece of 80 grit sandpaper and clean the 2 end plate where they attach to the center section of the starter. It also helps to put a ground wire from the block to the frame.Make sure the battery cables are good with no corrosion down inside these cables.

 

Ahhhhh...battery cables. That reminds me of what some old mechanic told me. You are right...the cables get corrosive inside of them....unlike on the outsite posts where you can see them and clean them...the inside of the cables get real bad if they are old or if you buy a cheap set. You need good heavy duty ones. I have had that starter problem happen to me and after taking the cables off, twisting them etc.. then putting them back on ..they seem to work just fine. But unless you get new cables..they will quickly revert back to that corrosive condition. jim
http://www.48f-1.com

 

I'm having a similar, slow cranking, problem on my 50 F1 with a 6 volt system. Where exactly is the battery ground cable supposed to attach? Mine goes to the engine block at the coil mounting bracket but I'm guessing that that's not right. Is it supposed to be the flat, bare copper variety? When you add a frame to engine cable, what two points did you use to connect it?
Thanks,
Dan

 

Converting to 12 volts is easy. The reason to switch is to get more power for cranking, plus parts are easier to find, like bulbs and batteries. To switch you'll need a 12V battery, 12V generator, 12V regulator, all the appropriate 12V bulbs and resistors for the heater and gauges. It's all really just swapping the old for the new. The starter can stay 6V, it won't hurt it. You can also leave your wiring as original wiring is more than able to handle 12V. As far as the generator, you have 2 ways to go. Either replace it with a similar one and get it to work on the brackets, or replace the internals with 12 volt parts, I've heard that you can use the internals from '63-'64 falcons w/ V8's. Converting my truck to 12V was the best thing I did, it started faster, lights were brighter, and I could add any modern electrical accesory I wanted, plus I know I can just go to any auto parts store and find replacement parts like a battery or light bulbs.
P.S. Remember that you'll also be changing the car to neg ground.

Gary
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46 truck-6cyl now, 302/C4 soon
46 truck-flathead 8, 4spd
47 truck-getting a 429/C6
57 Ford FL 500-4 dr-312/AT
70 Mustang fastback-351W/FMX
72 Olds Vista Cruiser-350/AT
88 Bronco II, 500,000+ mi.

 

The original ground cable goes from the battery post to the frame right behind the battery box. Alot of people just add a ground from the head to the frame. I would just use a spot that's convienient and a decent size. if you have good grounds and it's timed right, 6V starting shouldn't be a problem.

 

46 ford truck,
What about changing the points and condenser?
I once heard that if you change to 12v The points will burn up faster. Is this true?
What about all of the original guages: fuel, oil, battery, temp. won't they burn out if u put 12v to them? Just curious.
My truck Is 6 volt it does start right up and the lights are pretty bright. I agree with everyone else. as long as everything is clean there shouldn't be a problem with 6 volt.
Jerry


1949 F-1 pick-up

 

[updated:LAST EDITED ON 25-Feb-02 AT 07:19 PM (EST)]You can also run the starter motor on 12 v and leave the vehicle 6 volt. There's a lot of stuff to change if you convert and granted its probably better when you are done but if you drive the old truck on Sundays just for fun it may not be worth all the effort.

And yest you will need to carefully go through and upgrade some of your gauges or spend 500 for a package from one of the after market vendors

 

A couple of things need to be cleared up as there are some basic misconceptions every time this subject comes up; usually every other week.

Yes, 6V draws 2x the current of a 12V system but the power consumed in Watts is the same. The current is what requires particular attention to all primary circuit connections, not just grounds.
For 6V you want nothing smaller than #2 gauge cable; #0 if you can find it. Standard Brand offers a whole bunch of 6V cables. Any cable over 10-15 years old should be considered garbage. DO NOT use #4 or 6 gauge cables, they are strictly for 12V.

Ford used several cable paths and over time the corrosion takes its toll. Steel is a poor conductor as compared to copper; steel rusts plus the dissimilar metals generate their own corrosion.
I suggest running the ground cable directly from the battery to a well cleaned starter bolt. Then run another cable from that same bolt to a nice shiny frame hole, drill a new one if you can save even a few inches. Once everything is secure, cover the connection and surrounding steel with POR-15 or a similar product.
This is not the end of todays grounding lesson, the average truck requires attention to at least 15-20 grounds to function.

Converting to 12V is not always an easy way out and not always as cheap as some would have you believe.
Also old wiring may be already on the edge of a fire and increasing the voltage may be all it takes for a nice barbeque.

Points and condensers are the same on 6 or 12V. If using an original 6V coil the proper external resistor must be used on 12V to drop the voltage to the original level. A 6V coil from a Positive ground system can be used on a 6/12V Negative ground by simply swapping the primary leads.

If using a coil marked 12V only you may still have to determine if it requires a resistance, often built right into the wiring of many modern vehicles.

Ford 6V starters can be run darn near forever on 12V, IMO they were poorly designed for 6V. I always carry a 12V battery and cables "just in case" in my 54 F350. Just be real careful about connecting to the 6V battery, those boiling noises produce explosive fumes.

A clean and efficient electrical system and a ungummed up starter equal a happy Ford.

 

I recently converted my 51 over to 12 volt. Converted the generator by replacing the field coils and adding a 12 volt regulator. I purchased a 6/12 volt battery from Antique battery. This 12 volt battery has a terminal in the middle to supply 6 volt to where you need it. I have the starter, heater, headlights and am/fm/cd running off the 12 volt terminal. The gauges run off the 6 volt side. The 6 volt is supplied by a relay controled by the ignition switch. I don't have to worry about resisters or voltage regulators for the guages. I don't have my service manual here with me but you may want to pull the starter and make sure the drive is free. I beleive i read in the service book about a tension bolt on the drive for controlling how fast this pulls in.
If you switch to 12 volt use a newer style ford starter solinoid. This solinoid has a terminal for the ignition switch and another one to supply 12 volt to the coil for starting. your existing wire from the ignition switch would then go threw a ballast resister to drop voltage to the coil to 7/8 volt for running. By doing this your points will last longer. One more thing.. The starter button on the old system supplied a ground for the solinoid, on the new system you have to supply 12 volt positive. I did this by using another relay.

COST:
Generator field coils 35.00
Regulator 35.00
Relays (2) 10.00
6/12 volt battery 130.00