coil question
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which coil are you using now?
how much voltage do you have at the coil? if its between 7-10, there's already a resistor in-line. (you mentioned that you had about 8v before you took the old coil out.)
how did the auto parts guy tell you to hook it up?
how much voltage do you have at the coil? if its between 7-10, there's already a resistor in-line. (you mentioned that you had about 8v before you took the old coil out.)
how did the auto parts guy tell you to hook it up?
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I tested it last night and was getting 5.8 volts at coil. I'm returning the external resistor. Next is a new duraspark module and plugs. It still runs sluggish and some backfiring but not to bad. The coil is just one I got at carquest that was direct replacement. Just want it to run smoothly.
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you've got a couple of different issues, lets tackle them both.
1. bad coil (possibly)
2. your vacuum advance wasn't hooked up right.
since you went with a direct-replacement coil, you shouldn't have to do anything with resistors- whatever you had in place before is fine.
so- remove the new resistor, check your voltage at the coil again.
since your vacuum advance wasn't working before, i think you need to check your ignition timing, as well. no telling where it was set to compensate for the lack of vac advance. hook up your light and have a look.
report back with voltage & timing numbers.
1. bad coil (possibly)
2. your vacuum advance wasn't hooked up right.
since you went with a direct-replacement coil, you shouldn't have to do anything with resistors- whatever you had in place before is fine.
so- remove the new resistor, check your voltage at the coil again.
since your vacuum advance wasn't working before, i think you need to check your ignition timing, as well. no telling where it was set to compensate for the lack of vac advance. hook up your light and have a look.
report back with voltage & timing numbers.
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Okay have an update. After scratching my head trying to figure out why wiring doesn't match up and more conversation with the old Guy at carquest who seems fairly knowledgeable on the older trucks it seems I have an earlier 390 71-72 maybe. Points only no electronic ignition. So my duraspark module is not hooked up to this motor. So I guess its new plugs and check out the points gap. I'm getting just a little over 5 volts to the coil. Carquest Guy says I need 8. So I need to figure that out also. So now with the new details any new suggestions would be great
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wow...talk about muddying the water. 
Duraspark diagram
http://www.blindchickenracing.com/Ho.../duraspark.jpg
points ignition diagram
http://www.allfordmustangs.com/forum...ion-system.jpg
poke around, tell us which way you're wired up.
Duraspark diagram
http://www.blindchickenracing.com/Ho.../duraspark.jpg
points ignition diagram
http://www.allfordmustangs.com/forum...ion-system.jpg
poke around, tell us which way you're wired up.
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Tuned
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From: Near Nashille, TN
ahhh.. the Accel 8140C is about the same ohms as the Duraspark, so you'll be ok with the factory resister wire.
Funny, I have that exact coil sitting on my bookshelf (it's good for nothing else). For 2 years, I thought I had a vapor lock issue... if I was idling in traffic on a hot day, sometimes it would die and I couldn't get it restarted. If I'd let it cool for a while, it would restart just fine. Turned out it was the Accel coil getting hot and loosing spark. I bought a $20 Duraspark replacement coil and haven't had any issues since.
Funny, I have that exact coil sitting on my bookshelf (it's good for nothing else). For 2 years, I thought I had a vapor lock issue... if I was idling in traffic on a hot day, sometimes it would die and I couldn't get it restarted. If I'd let it cool for a while, it would restart just fine. Turned out it was the Accel coil getting hot and loosing spark. I bought a $20 Duraspark replacement coil and haven't had any issues since.
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ok- i'm going to be over-cautious here, since your wiring is a bit...different.
#1. pop the distributor cap and have a look.
duraspark distributor looks like this:
http://www.fordmuscleforums.com/atta...tributor_3.jpg
points distributor looks like this:
Ford points distributor image by 10w30dna on Photobucket
#2. i'm wondering if you have a resistor wire AND an external resistor. follow the wire from coil "+" through the firewall, to the ignition switch. do you have a fat pink wire in there somewhere? is there also an external resistor?
#1. pop the distributor cap and have a look.
duraspark distributor looks like this:
http://www.fordmuscleforums.com/atta...tributor_3.jpg
points distributor looks like this:
Ford points distributor image by 10w30dna on Photobucket
#2. i'm wondering if you have a resistor wire AND an external resistor. follow the wire from coil "+" through the firewall, to the ignition switch. do you have a fat pink wire in there somewhere? is there also an external resistor?
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Its definitely the points distributor. I looked for engine #s. Could only find the 40 352 stamped in block. By the dipstick there is a 19 did stamped in. The intake manifold is an edelbroch performer 390. Where would the actual engine tag be? I'm not finding anything else but the #s on the motor mount block. I'll trace the ignition wires after work
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Well I think I finally got it going. Changed all the plugs? Found some of the spark plug wires not pushed down in the cap completely. That definitely made some improvement. Then I set the timing and now it runs great. Now I think my alternator crapped out. Seems like I get one thing working properly then something else goes. Hopefully I won't have anything left soon
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It went up after putting some charge on the. Putting a new alternator in tonight and I'll recheck. It does have the pink resistor wire. If I can't get 8 I could bypass that and use an external resistor and see how that works
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