Ignition Issues - Ignition Switch? Pickup Coil?

jrdoj · Last edited by jrdoj on Sat Apr 21, 2012 5:30 pm; edited 2 times in total

EDIT: You're welcome to jump straight to the March 26 post and read on from there as all this info has been ruled out. Thanks for the input.

First off, I'll just admit that my entire ignition setup (like many things on my car) was hastily set up 10 years ago at age 20 or 21, when my only concerns were saving money (to put toward beer) and getting the job done fast (so I could drink beer). I installed electronic ignition (the orange box - what brand is this?) and at some point replaced the coil (Checker Auto's cheapest option, and I likely said nothing about the electronic ignition; it may have been before the electronic ignition) - that's all I remember for sure.

So, I was following this recent thread (which was helpful), but I don't know if I should be expecting the same readings for my basic/stock coil that wjajr mentioned, or something different.

I disconnected my coil, set my meter to OHM, and my situation is this:

With my multimeter set at 200, and the black VOM probe on (-) and red on (+), my low voltage circuit reading is 1.8.

With my multimeter set at 200k (I don't have a 20k setting for some reason), one probe in the center hole of the coil, the other on the (+) terminal, my high voltage circuit reading is 9.1. Now, does that translate to 9,100 ohms or 90,100 ohms?

Do coils, like batteries, expire more quickly in Arizona heat? And if it's time for a new one, should I be searching for something in particular to jive better with my electronic ignition?

_________________
J.R.
Tucson, AZ
'68 Dart 270 with a '76-'80 engine

SlantSixDan · Post subject: Re: Ignition/Coil Issues (Fri Mar 16, 2012 12:29 pm)

The orange box isn't very good. You can do much better without spending a whackload of money; see HEI upgrade . Coils might be marginally more likely to expire sooner than later in a hotter rather than cooler location, but not substantially so.

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By choice: Canadian citizen, 1st class

jrdoj · Post subject: (Fri Mar 16, 2012 1:02 pm)

I just ran across your article about the HEI shortly before you replied. I'm going to look in to that for sure. Any thoughts about the multimeter readings? Is this one expired, or is it even possible to tell without knowing the part number?

_________________
J.R.
Tucson, AZ
'68 Dart 270 with a '76-'80 engine

Mroldfart2u · Post subject: (Sun Mar 18, 2012 7:55 am)

jrdoj · Post subject: (Thu Mar 22, 2012 5:32 pm)

Oooookay. I took what I thought I'd learned and Mroldfart2u's advice and got a new ignition coil (Napa Echlin IC27). Installed it. Figured I should check the readings with my multimeter....

Primary side = 1.6 ohms

Secondary side (again, with multimeter set at 200k) = 9.8

Roughly the same readings as my previous 'bad' coil. What is going on here?

Also, I don't recall if I updated the ballast resistor 10 years ago, so I tested it and that reads 1.6 ohms resistance as well. Might that be contributing to the problem?

I was good at math in high school, but only insofar as my ability to follow procedures and formulas to get to the correct number. So I don't really know what I'm doing here - I'm just following steps and looking for results based on what I've read in other threads.

Any insight?

_________________
J.R.
Tucson, AZ
'68 Dart 270 with a '76-'80 engine

SlantSixDan · Post subject: (Thu Mar 22, 2012 11:43 pm)

1.6 ohms is correct for the ballast resistor. I don't see anything wrong with your original coil readings. Coils seldom go bad.

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By birth & parentage: US citizen, 2nd class
By choice: Canadian citizen, 1st class

KBB_of_TMC · Turbo Slant 6 Joined: 09 Sep 2005 Posts: 848

While coils seldom fail spontaneously, it's been my experience that oil-filled canister coils do go bad with age - usually after around 1 (US=1e9) billion sparks you start to get some internal breakdown.

Years ago, a local diagnostic shop came to our all-Mopar show and tested show cars for free with their fancy scope; ~3 of 4 were told "bad coil". I asked the techs, and they told me that coils are a wear item and that these 30 year old coils were just "worn out". I usually coils ~100,000 miles or less.

jrdoj · Post subject: (Mon Mar 26, 2012 7:25 pm)

Well, the similar readings do make me think replacing the coil may have been unnecessary; I couldn't remember if I had installed it (the one I just pulled) before or after switching to electronic ignition.

However, I replaced it at the same time as I was upgrading to some Magnecor wires. The car now seems to fire instantly, but won't actually run anymore. Other research on this board leads me to believe this is either the ignition module or the ignition switch. I'm upgrading from my old orange box to the HEI per Dan's suggestion. We'll see what happens and I will follow up here.

Thanks for the input, gentlemen.

_________________
J.R.
Tucson, AZ
'68 Dart 270 with a '76-'80 engine

jrdoj · Post subject: (Fri Apr 13, 2012 8:12 pm)

I installed the HEI, with the power relay. The car is doing the same thing as before - firing, but not running. I hope the fact that it's still firing indicates I installed the HEI correctly.

But, this now leads me to believe the ignition switch might be at fault. I recall replacing it about 15 years ago. How do I go about testing the ignition switch at the run position?

Also, while I have your ear, after I pulled the orange box ignition, I noticed that the wire going to the (+) side of the coil (a blue one) was still attached. It's coming from the original loom and served its purpose for both the points and the electronic orange box systems. It's now unattached. Does it serve any purpose at this point?

_________________
J.R.
Tucson, AZ
'68 Dart 270 with a '76-'80 engine

jrdoj · Post subject: (Sat Apr 14, 2012 7:51 pm)

Well, nevermind that bit about the blue wire. lincparts pointed out in a private message that it was the "run" wire. I thought for a second that was going to solve the ignition problem!.... but no such luck. I now have it attached to the (+) post on the coil along with the relay "87" wire and the wire to the "B" terminal on the HEI. Only the "C" terminal wire from the HEI is connected to the (-).

But now another strange thing is happening: the red oil light is on, and won't go off! Even after I pulled the ignition switch so I can start checking for continuities. What gives????

_________________
J.R.
Tucson, AZ
'68 Dart 270 with a '76-'80 engine

WagonsRcool · Post subject: (Mon Apr 16, 2012 1:04 pm)

I believe that you have created a "latch relay" system. If the relay is triggered by the ign/ "run" circuit, & the relay output now goes to to that same run circuit...once you turn it on then it will stay on until you pull the relay.

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63 Valiant Wagon
225 - 4 bbl

jrdoj · Post subject: (Mon Apr 16, 2012 9:58 pm)

jrdoj · Post subject: (Sat Apr 21, 2012 4:34 pm)

1. Okay, so continuity among the wires in all the obvious places seems fine. But I was messing with the ignition switch some more and testing for continuity in the various positions, and I'm puzzled: with the key in the 'run' position, I hold the first probe to the BAT terminal and the second to the IGN1 terminal and I get continuity; but, when I move the second probe over to the IGN2 terminal, I don't get continuity; leaving the probes where they are, I then crank the key to the 'start' position, and then I am getting continuity; and, of course, I get continuity as well as when I hold the second probe to the ST terminal (meaning the IGN2 and ST terminals are responding the same way). Should this be? (See photo below for a visual.)

2. The pickup coil: before I checked the resistance, I read this should be between 150 and 900 ohms. With my meter set at 2k, I get a reading of .293. It's hard to tell when people are just speaking in shorthand as I don't have much experience with these readings, so does my reading of 293/1000 ohms fall within the 150-900 range, or is it ridiculously low?

3. If I need to adjust or replace the pickup coil, what should the gap for a '76-'80 engine be?

4. Any advice on how to prevent my power relay from "latching" (see previous post)?

_________________
J.R.
Tucson, AZ
'68 Dart 270 with a '76-'80 engine

WagonsRcool · Post subject: (Sun Apr 22, 2012 4:11 pm)

1) Pretty much correct. BAT is the power into the ignition switch. In the Run position Bat connects to Ign1 & Acc. As you turn to Start, the switch shuts off Acc, then turns off Ign1 as it connects Bat to Ign2 (this bypasses the ballast resistor). It also connects to St as you fully reach the start positon.

2)For your meter reading, on the 2k range (0-2000 ohms) you take .293 & multiply it by 1000= 293ohms (if your meter reads 1.2 on 2k scale = 1200ohms) So 293ohms is within the given specified range, between 150 & 900 ohms.

3)As I recall, ignition pickup gap is .008" to .010" . Dan or someone else can correct me, but I've always used a brass feeler gauge to set the gap at .008" (8 thousanths ) while the vacuum advance was half-applied (that puts the pickup at its closest point to the reluctor)

4)The relay is just a switch that connects the battery (pin 30) to the output (pin 87) when it's activated. If you connect the output (pin 87) to the run circuit & use the run circuit to trigger the relay, then once you turn the ignition switch on, the relay "triggers" itself. So you don't want to connect pin87 to the run circuit.

_________________
63 Valiant Wagon
225 - 4 bbl

jrdoj · Post subject: (Thu Apr 26, 2012 11:04 pm)

Thanks so much, WagonsRcool, for the thorough explanation. That helped a lot. I've mostly refocused my efforts on the HEI and have posted here on that. As you'll see, I don't know how to avoid connecting pin 87 to the run circuit.

Another question, though: should I have continuity across a voltage regulator with the car off? Because I don't. Yet another theory.

_________________
J.R.
Tucson, AZ
'68 Dart 270 with a '76-'80 engine

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