Converting from points to Pertronix, confused by resistor wiring

Bluemike

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The first thing I'm doing is putting in a pertronix points conversion, and I get to the resistor, I also ordered a new Pertronix coil because I just want to do it right. SO.....
On the resistor is: on one side a single wire 12V feed on/off with the key, the other side are 2 wires joined. I understand one of these goes to the coil, where does the other joined wire go? If I jump the resistor as recommended, does the other joined wire go somewhere that could damage something?
Seems like the first 60 years of my life I got away with "ignorance is bliss", I'd just jump them all and forget it. Now in the last three years my luck's running out, without asking I'd fry some expensive irreplaceable thing I'd have to tear half the car apart to fix, and someone would say, "That was dumb, everybody knows you can't do this..."

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MrMoparCHP

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The side with one wire goes to the key, the other side the brown wire goes to the key and the blue wire goes to the coil, and voltage regulator.

When you turn the key to start it bypasses the ballast (brown wire) to give full 12v to the coil on start.


Alan
 

Big_John

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No ballast resistor needed with the Pertronix per every instruction sheet that they have that I've ever read.
 

Bluemike

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The side with one wire goes to the key, the other side the brown wire goes to the key and the blue wire goes to the coil, and voltage regulator.

When you turn the key to start it bypasses the ballast (brown wire) to give full 12v to the coil on start.


Alan
Thank you!. So obviously I can just stealth a bypass, leave the resistor look like it's hooked up.
This resistor I think is perhaps in series with the coil? I measure it unplugged THROUGH the resistor I get around 12 volts, WHERE it hooks to the coil same, BUT when I hook it to the coil and ground the other side of the coil I get` 8.7. The Pertronix coil calls for as little as 8 but recommends 12, might as well give it all it can take. I'm a firm believer that ignition accounts for a big part of increasing performance.
Old timers used to say "put mothballs in your gas tank". That I don't plan on trying. Looking forward to hearing from you in the future
 

Loadrunner

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Sadly ignorance is not bliss with points ignition or otherwise. To me, electronic is even harder to troubleshoot and more daunting if not flatly impossible to repair.

Properly installed, a good quality set of points/condenser lasts for years.

In a distributor with a reasonably tight shaft, a working vacuum advance and mechanical advance mechanism, you'll get all the performance you need, and two cheap parts in your glove box can get you on the road again. Three if you count the ballast resistor and I'm pretty sure one of Moses' missing commandants was to - in booming voice - Thou shall always have a ballast resistor in your glove box, although even better already hanging in position as a spare, making you look either really smart, or paranoid, depending on the audience.
 

300rag

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... So obviously I can just stealth a bypass, leave the resistor look like it's hooked up.
...
When I did mine I soldered in a short length of #10 wire across the back side of the terminals in lieu of the resistor. Unless you pulled it off the firewall you would never know that it has been bypassed.
 

WOT440

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When I did mine I soldered in a short length of #10 wire across the back side of the terminals in lieu of the resistor. Unless you pulled it off the firewall you would never know that it has been bypassed.
Did the same.
 

Bluemike

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This problem is solved. Thank you for all your help. I do agree points do a fine job unless you're bouncing the tach at 7,000rpm.
Maybe the term should be, "No good JOB goes unpunished". Now the alternator only charges when it's in the mood, obviously I bumped some wires. Holding a screwdriver to the back of the alternator suggests it's doing something, (showing magnetism) but the volt meter stays at 12.5 volts running or not, dash gauge doesn't move lights dim etc. The alternator appears new which doesn't mean it's good. It has the old mechanical relay black box,
It's been 30 years since I played with this stuff but I'm sure a newer style electronic one can be swapped in, then I guess I can start chasing wires?? I would be grateful for any advice.
 

Loadrunner

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Easy peasy.

The reg provides "field current" to the armature field coils via slip rings to a pair of brushes, one hot, one ground.

Make a short jumper to go from the Alt + to the Field + flat male terminal on the back of the alt, no need to disconnect anything, while running, apply the 12VDC to the field terminal, this is known as "full fielding the alternator"*, and you should immediately and audibly drop some idle as your voltmeter could show up to 15 volts.

If the alt doesn't do anything on a full field test, something is gunnybag inside, open armature, shorted or open stator coils, blown diodes, etc, all super easy to diagnose and fix.

If you do get a decent reading by full fielding, your reg is out.

You can switch to a Chrysler SS reg - or not- while changing from a "Roundback" = harder to service, diodes are pressed and soldered in, to a "squareback" = easy to service, the diode trios are removable with a 1/4" socket and easily available.

The old roundback is internally grounded: A circuit, and the squareback is not: B circuit, which means you have to make a short jumper lead from one of the body screws to the negative post of the alternator to ground it.

You can see the added external ground here on my alt, a squareback running a mechanical regulator (EMP proof?) without any problems at all.

Make sure to keep a fresh and properly tightened Gates alternator belt on your engine, the alt can draw prob near 5hp at full tilt.

P1090507.JPG



* Full fielding on the old Delco 10SI was known as "raping the D hole" as all you had to do is stick a straightened paper clip through a little D shaped hole in the back.
 
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