Sorry to start a new thread related to my other thread, but I believe I know the solution to my other problem. The power feed to my ignition is currently hooked to only a run power source on the back of my ignition switch; it's a Mid-Fifties12V switch with four posts on the back (one in from the battery, one for the accessories position, one for run, and the last for crank). I need a power source, to feed the ignition, that is hooked to both crank and run. Can I just run the power feed to both posts? Or, is there a better location to tap into?

 

i have not a clue !!!! maybe if you posted some pics. of your truck HINT HINT. LOL

 

Many ford solenoids have an aux contact on the side that will deliver a full twelve volts only when the solenoid is closed and cranking the engine. This post is usually connected to the ign. coil thus bypassing the resistor at the coil. It is designed to give a full 12 volts to the coil while cranking to increase available spark at the plugs. The solenoid I'm referring to has four connections, two heavy lugs and two smaller lugs. One small lug comes from the "start" on keyswitch and the other one goes to the ignition coil. If you have only three connections on your solenoid you could always use your heavy lug going to the starter to provide your 12 volt during crank.

If you do it the way you suggest, by connecting the "run" to the "crank", you will be providing power to your starter solenoid whenever you turn the key on and you don't want that.

 

Hi It would be nice to have more info. What engine, 6 or 12v, what type of ignition system ect.? I'm assuming that it is a standard type 12v ignition with a resister to cut power back to 6 or 8v at the coil. If this is the case I don't think your problem is the ignition switch. I think you should have a solenoid with two small posts. the wire from start on switch to one small post and the second small post on solenoid should have a wire going direct to the coil to supply full 12v when starting. I think you are missing this wire. With the info available I'm only guessing and I am NOT a wiring wizard. Hopefully someone that is will come along. Hope this helps.

 

Oops- didn't see your original post. fixnair is saying the same thing only better. We must have been posting about the same time. His is a much better explanation.

 

If your switch doesn't supply power to the run/coil at the same time it supplies power the the crank/solonoid/starter you can run a extra wire from the output of the solonoid to the coil. The starter switch should also have a spring back from the crank position to the run position internally in the switch. Maybe a bad switch. chuck

 

That is the solenoid that I have, so I'll make a "jumper" and jumper the I post directly to the coil and see what happens. The Start is currently hooked up. Under my present wiring, the coil is getting fed from just the RUN post.

 

Thanks, I'll try the solenoid jumper. The switch is new and seems to check out fine.

 

Dale, I've been stalling on this. I'll see what I can post up.

I looked for my camera and I must have sat it somewhere and piled stuff on it.

 

OK- I think I have it figured out. I hooked up my coil feed to the "coil" wire in my after-market wiring harness(it's hot in run and start). That by itself didn't get me spark. However, I also jumped 12 V to the switch input on the fuel pump relay to kick the relay; after I did that, I got spark. I was planning on getting an inertia switch and tracking down the fuel pump next. So, apparently if your fuel pump isn't hooked up through the computer (which mine currently isn't because (I wasn't seeing 12V through that circuit)the computer won't give a SPOUT signal to fire the coil. I guess I'll go and play with the fuel pump circuit next. Thanks for all of the input; I was just telling the wife that I'd be lost without all of the resources on-line.

 

Here's the latest update. After further exploring of my fuel pump relay, I discovered that it get's it's input voltage from the EEC (computer) relay. Well the computer has it's input voltage and it's common(constant) voltage, but no output voltage to the fuel pump relay. So, I'll stop by O-Reilley's and pick up an EEC relay tomorrow. Theoretically, that should "fix" my no spark issue. We'll see?? Any thoughts on this?

 

LOL grab a bottle of Ibuprofen too! Sounds like you are gonna figure it out, thats cool !

 

I bought the EEC relay and put it in after work. Now, it fires sparks like crazy. I even put tranny fluid in last night now for a little gasoline and we'll see what happens. Per an earlier thread, there are two firing orders for the 5.0 L. I have it set up per the Haynes manual for an 87 Tbird but the HO motor one is probably the one I need? I'll try the current firing order prior to switching the wires.