Factory replacement coil?
 

70 T/A 4-speed

Stock 400

Replaced the points with a Breakerless SE kit about 5 years ago and it's been great

Crisp starts and I haven't had to touch the timing since the install

That being said, I was leaving OSW earlier tonight and noticed a bit of a stumble when accelerating.

Pulled off into an open parking and she died.

Cranked her up and she started, but had a severe misfire like she was running on 4 cylinders, then she died again.

Popped the hood and noticed the coil was hot to the touch

Checked the ring terminals best I could (it was already dark), but they felt tight.

Pulled the coil wire and it was also fine.

Let her cool for about 15 minutes, then fired her up and she was good to go again like nuthin ever happened.

Hauled ass home and powershifted through the gears without issue.

Have yet to check coil resistance, but I figure I better pickup a spare regardless.

Thing is, I remember when I was installing the Breakerless kit that they suggested only using a factory spec coil and not an MSD or Accel.

What would be the best stock appearing coil that's compatible with the Breakerless module? (I believe it's like 1.3ohm or so)

Go to a NAPA parts store and buy a IC12 coil.

Also just in case I would check that you charging system is not outputting excessive voltage .

I would also confirm that once the car has been driven a while that your 9 volts to the coil is not dropping down.

OK, so I cranked her up early this morning and pulled her outside to check her out before the sun starts baking

After a little digging, I found that the PO did one helluva hack job bypassing the resistor wire and running direct ignition source from the fuse block to the coil (wonderful)

Not sure how I missed this when installing the Breakerless kit or how it even lasted all these years running as is

There's a spot on the firewall that looks as though a ballast resistor was mounted previously, so I'm just gunna throw one in there for now and deal with rewiring everything on my next trip down (only here for a few weeks)

Sounds like the way to go, but I would also check out the wire inside the Dizzy going to the points that runs under the breaker plate.

In these unseen places the insulation has been known to dry rot off that wire and then at times when the advance plate moves or the motor vibrates enough shorts that wire out to ground and killing the spark.

If the previous points were causing problems it was probably the lack of resistor wire roasting them frequently.

NAPA was closed today

O'reilly's didn't have anything in stock

Advance had a generic R-11 crossed to CarQuest

Installed it and it dropped voltage at the coil down to 11.4v at idle (battery voltage is 14.6v running)


Don't really have the time to dig much deeper, but here's video from years ago when I installed the Breakerless kit

https://www.youtube.com/watch?v=mpdc3HBXgqY


And here's a short dash cam video of me taking her for a little romp after installing the ballast


https://www.youtube.com/watch?v=256vQUG_MVU



Isn't 11.4v too high for the Breakerless module?

I would think that 11.4 is ok short term with a unit that’s designed to be a drop in for points since that’s what a points system will have when cranking to start the motor, but for long term once the motor lights off that 11.4 might be detrimental I just can’t say for sure.

I would only feed it with 9 to 10 volts when it’s running when you get back to working on it seeing as that’s what it was made for , I mean unless the installation instructions said different.

OK, just spent the last 30 minutes rippin through the gears on our back roads and she's running great

Checked running voltage at the coil and it's still at 11.4v

Went home, shut her down, turned ignition on and she's seeing 13.2v (battery is at 13.4v)

Coil is warm, but not hot to the touch like last night (it's like 102* here btw, so everything feels hot)

Resistor feels warm as well, but here's the thing......

I pulled the leads off and it reads at .5ohms (wtf)

I checked online and the part number on the box checks out as a cross for the RU-11

Unless they put it in the wrong box, I'm guessing it's a thermal ballast?

Gunna need to find a fixed 1.8ohm unit

With a reading of 1/2 of an ohm it would seem to be for a Mopar electronic ignition system.

summit has a G5218 that’s 1.6 ohms but it uses ring type connectors, not spade.

A MSD 8214 is .8 ohms and uses spade .

Most breakerless aftermarket (and factory GM) ignition systems are designed for full alternator voltage/current running.

What brand ignition system do you have and what does the instructions says about voltage to the coil?

Breakerless SE module kit on factory points distributor and coil

AFAIK, it should be 8-9v at the coil when running

Ok, this unit is to be run with the original ignition harness including the resistor wire.
About 11 volts at coil + running is perfectly fine and whats to be expected using the resistor wire and an original 2.0 Ohm coil.
Remember, the resistor wire reduces current as well as voltage.

No that’s not the case!
If something electronic is spec’ed for needing for example 12 volts and 3 amps of current if you deny it 2 volts it will try and draw more then its normal 3 amps it needs to get back to performing properly if it can.

This is what makes electronics run hotter then it should which in term reduces the life of the item that’s being powered.

Sometimes it helps reading the instructions:

https://breakerless.com/pdfs/92965073.pdf

All of what he said in post 15.

If the iriginal ballast resistance wire has been changed out and folks been swapping stuff, try a Standard Ignition RU-10 instead.

I think you’ll find it closer to what you’re looking for.

OK, so I picked up an AC Delco F1104 ballast on Amazon and it read at 1.4ohm

Popped it in and it's reading 9.4v running (14.4v at the battery)

Of course this meant having to add a bypass for initial starting, so I just added a hidden momentary switch under the dash for now.

A stock GM starter solenoid has a 2nd small terminal on it to do this same thing automatically when you back your ignition key off of the crank position.

At the "R" terminal on some later GM starter solenoids on specific vehicles is a yellow wire giving full battery voltage when cranking to + on ignition coil for easier starts.

Other vehicles has the "R" wire at the ignition switch giving full battery voltage while cranking:

No time to dig any deeper this trip, but she's running great again

Already put her in storage

I'll mess with her again on the next trip down

I have a real nice 238 coil if needed
delco remy

Scott
206 465 9165

A NAPA IC14 (or equivalent) has an internal resistor in the coil. That should protect the pick up. With the better part of battery voltage, itsvgoing tonrun strong

According to the instructions for that unit, posted in this thread, they want the COIL to have 1.2 to 1.8 ohms of resistance. They ALSO want the coil fed with a resistance in the power-supply wire--the original resistance wire, or a 1.2 to 1.8 ohms ballast resistor.

Therefore, TOTAL intentional resistance in the ignition coil circuit would be 2.4 to 3.6 ohms. A resistor coil by itself won't be enough; neither will a typical ballast resistor by itself. This system needs both the ballast resistor AND coil resistance. Which--to be honest--doesn't make any sense because they claim that the ignition module is "Over-voltage/over-current protected."

Overall, NOT my first choice in an electronic ignition system. God bless Genuine GM HEI--protected (at least short-term) to ~18 volts.