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-   -   65 ford f100 or 68 ford f250 ignition system (https://www.fordforum.com/forum/south-west-57/65-ford-f100-68-ford-f250-ignition-system-45952/)

ray77 Aug 6, 2022 10:20 AM

65 ford f100 or 68 ford f250 ignition system
 
On either of these old trucks, the ignition should be the same. When the key is held in start position, is a 12 v signal sent to the starter solenoid in the inside fender, circuit inside solenoid closes , simultaneously sending 12 volt signal to starter and ignition coil?

hanky Aug 6, 2022 11:01 AM

If you had access to a multimeter you could easily get an answer to your question.

You could measure the voltage at the positive terminal on the coil, both when the key is turned on and then when cranking the engine.
If it has a resistor in the line from the run terminal on the ign sw , you would read 6 volts at the coil positive terminal when the key is turned on.
If no resistor , you would read 12 volts.

If it uses a resistor , when cranking ,the coil gets 12 volts from the starter relay when cranking for easier starting.

raski Aug 6, 2022 01:35 PM

There is a resistive wire serving as a ballast under the dash, otherwise the points would be short lived with the coil having 12 volts applied during run.

ray77 Aug 15, 2022 11:53 AM

68 ford f250
 
Hello Hanky
I have a multi meter , but not digital. If i clip the positive (red wire) on my meter to the positive terminal of of the ignition coil, what do I clip the ground (black) wire on my meter to? Before i do anything, what reading do I set my multi meter to.? If it turns out that there is a resistor (ballast resistor?are they the same thing?) coming from the ignition switch start position, where would I start looking for that thing? Somewhere between the dash ignition switch and the starter relay on the fender under the hood or should I look somewhere else? Had driven old ford trucks for years, but when you start rebuilding one, it's quite a different story. lol. New to a lot of this and surly appreciate you and others input. thanks again

hanky Aug 18, 2022 05:57 PM

Sorry for the late reply.

The best place to clip the black wire(Ground) is on the battery negative terminal or a clean piece of sheet metal.
You should set your meter to read DC Volts and the closest selection to 12 volts . As long as you don't select a position under 12 volts.

A resistor wire (resistor is built in to the section of wire) and ballast resistor , in this case, have the same function, to bring battery voltage ( 12 volts) down to approx. 6 volts.
This set up is used only for ignition purposes. Coil is designed to operate at 6 volts all the time except when starting when power from the starter relay will send 12 volts to the coil for easier starting.
If you can, we always appreciate pictures of your project, thanks.

ray77 Aug 16, 2023 07:05 PM

On a '68 f250 what size are the brake lines and fittings. Also does anyone know if anybody makes a flex brake line instead of a rigid line that you have to bend all over the place to make them fit? thx ray77

hanky Aug 16, 2023 08:14 PM

If you remove the line in question, measure the approx length, now you have some idea of what length you need.
Most NAPA stores carry various lengths of brake line that are very easy to bend and form .They come with the fittings already on them and double flared .
Hardest part is getting off the old lines.


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