I'm more confused now. (No jokes!) The resistor wire aka "pink wire" is bypassed during start, so it's "hot" whenever the engine is running. That would need a fuse, except, the ignition system is already fused, (or should be) - there is no reason to add another fuse?

 

Why would you want to put an inline fuse in this circuit? With that type of thinking, then why wouldn't we put inline fuses in every "hot" wire running to every device on the truck ie: every light, horn, switch ect? Simple, because it's not needed. If you put a fuse in the resistor wire circuit and the truck wont start you'll be thinking...hhmmmm....is it that fuse I put in, is it a bad connection...hhhhmm Just replace the pink resistor wire with a new wire from the back of the ignition switch to the coil and be done with it.


Full 12 volts to the coil in the run position for a pertronix equals a happy and working pertronix.

 

My point being it's already fused. It's gotta be.

Might be on the other side of the ignition switch, but it's fused just the same? I agree that Pertronix and a hot coil is the way to go with full 12 volts. And there is way too much mystery about the "pink wire", it's just wire. It's designed to get hot.

 

Yes, the main power wire running to the ignition switch is fused by a fusible link located at the starter relay. This is how the ignition circuit is fused as is the whole truck, through various fusible links at the starter relay location.

 

I think they wanted to fuse the resistor wire to protect the resistor.

when i installed the pertronix, I had no clue there was a resistor originally.

Back to the original post from pastor Dale. He is using the oem ignition system. Which is supposed to use an 8v ignition? The last owner of pastordale's f150 had strait 12v to the coil which would over heat the coil? That could have been causing the original intermediate shutdown.

So is the ignition module stock for a 75 f150?

I think when he got the truck it had some sort of aftermarket ignition plate under the distributor cap? (The wires to the coil broke on it)
Which pastordale replaced with oem?

 

See above for answers to most of your questions.

 

I would still use a fuse if replacing the resistor wire with a straight wire. A 10AMP fuse should do the trick.

If your keeping the resistor wire, then no need for a fuse. Voltage should be around 8 volts when running, and 12 volts when starting (I feed from starter relay).

Give the coil and ignition system what it wants, either resistor wire for OEM or full voltage 14 gauge wire for them aftermarkets.

Original wiring shows no fuse going to the resistor wire, except the large fusable link going to the ignition switch. And the wiring behind that would become the fuse if anything crappy happens. I'd still want a fuse, because I like them blowing there, and not my wiring

whatever you do, be careful with those nice dents and bumps and let those chebby's burn ;D ... wait.. what am I talking about I got chebby parts on my efi'd ferd :P and VW, and Jeep.. and Chrysler... parts

edit: been perusing various shop manual wiring diagrams, and it seems the coil ignition supply (through a ballast resistor) is not fused until the wasted spark and coil on plug types. And those coils are fused by a 15 AMP fuse, so... there ya go. I fused mine to be on the safe side, but might go with a 15 amp instead of a 10 amp.

 

Lol I'm running a chebby one wire chrome 180amp alternator shh don't tell. The 3g 130amp I put on was pushing out 18 to 20v lol so I ditched it. Tried running a different voltage regulator(the part with the brush's), it brought it down to 17v but still no good.

I can't lie i'm a Honda guy i have just about everything Honda makes. I can build a gsr 1.8l to put 179hp to the wheels with oem parts with my eyes closed. I have been known to completely build a pgmfi obd1 vtec engine harness from scratch. I can chip and tune an obd1 ECU just fine.

Now I'm learning these trucks, coming from an efi setup things like different voltage ignition systems are foreign to me.

But my 82 Honda trail 70 has points i got that down. Lol it had an AC 6v ignition with 6v dc lights.

Pastor dale don't have points he had like the my 79 f250 has with the ignition module and the cdi style distributor i guess?? Anyways he don't have points.

 

My 1975 390 has a solid state ignition, no points. I believe it is factory. put a resistor in the hot wire going to the coil. Seems to work, sitting in the driveway. I need to make it neat and put everything back before a road test.
Thanks for all the help and advice, I was out of ideas.

 

frustrating, A little solder, a little tape. Now it wont start.
Tomorrow is another day

 

Where did you get the resistor? a Ford replacement, or a radio shack special?

as a diagnosis, you could run a jumper from the battery to the coil (kinda like hot wiring it).

 

radio shack special.
Raining hard today, when it lets up I will look at it again. I might go down to the parts store and find one for an auto.

 

Drag a multimeter along with you, my '78 wiring diagram shows a 1.05 to 1.15 Ohm resistor.

Maybe it's a part that can be ordered aftermarket or from ford. I think this is the best way as it keeps it factory.

 

Thanks for the time & help.

 

What wattage resistor did you use? Seems to me it would be on the order of 50 or 60 watts.