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Discussion Starter #1
So I just reinstalled the 289 back into my 64 Falcon and while doing so I cleaned up some old hacked on wiring under the dash. This car had the ignition switch bypassed by the previous owner, and a simple toggle switch and starter button installed. It ran fine before I pulled the motor. This is whats happening: Car will run on start power only, I ran a jumper directly from batt pos to coil pos and while cranking I jot a little shock off the carb linkage. I mustve screwed something up under the dash. How can I basic wire this thing just so it will run? And where does the I and S terminals on the starter solenoid go to? Thanks alot.

Matt
 

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Think of the starter solenoid as a relay. The S post is the trigger for the solenoid that actuates the starter (switched at the ignition switch). The I post is a 12V source for the ignition that is only powered while the solenoid is triggered and the starter is engaged. It sounds like this is at least part of your problem. The original circuit has a 9V power wire in run, and 12V in start. 12V is a hotter spark to aid in starting, but the hotter spark reduces the life of the points in the distributor. 9V while in run is achieved with a resistor wire.

This is probably why someone had wired around it before. Check at the ignition switch and find the wire that is for the coil. Check for continuity between that post on the ignition switch and the (+) wire on the coil. One of your problems is in that circuit. Any chance that the + and - wires on the coil are switched?

As for getting shocked while touching the carb, I'm not sure if that is related or separate. Check that the engine is well grounded via a substantial gauge wire or cable.
 

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So since I'm not running points is it safe to say a full 12v to the I terminal is ok?
Not sure if this is what you meant - but it's not 12v TO the "I" terminal, it's 12v FROM the "I" terminal, and only when cranking. If you are already running no resistor to your coil, you can delete any connections to the "I" terminal, as your coil is already getting full battery voltage during cranking.

To be sure this is acceptable, what are you using instead of points, and what coil are you using? The reason I ask, is because (stock) resisted power does help save the points, but it primarily protects the coil if the ignition is ON but the engine is not running, such as if the engine stalls. In that condition, non-resisted power can fry your coil by overheating it, if power can flow through the coil without the engine running.

David
 

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Discussion Starter #6
It's an MSD ready to run with a blaster 2coil. It's wired like this: main power to toggle(yellow) with a jumper to the starter button, so you can crank with ign off. One wire directly to coil from on side of switch, no resistor. I'll have to look at what heads to starter.


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Depends on your blaster coil. I've seen blasters that need a resistor, and I've seen them that do not.

Dave is right, the I terminal is ONLY active when the solenoid is engaged and it gives full cranking battery power to the Coil+ while the starter is engaged only.

See your Blaster instruction pack, it will either say run a ballast resistor or ruin direct 12V.
 

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Discussion Starter #9
So, it was wired in such a way that the I terminal had 12v running to it. The electric choke was also wired to it! All eliminated an working great.


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That's funny. the I terminal IS technically getting a couple volts from the coil + feed wire when running, but ONLY when running and ONLY when cranking. The I terminal wire is JOINED in the engine bay side of the harness to the pink wire at the joint where the pink resistor wire is spliced into the red wire with black stripe for the Coil+.

Once all is worked out, make sure that the ONLY continuity on the I terminal of your solenoid is that with which is between the I term and the coil + terminal.
 
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