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Ignition issue

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Larry302

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I have a 302 PCM, 1980’s style set up but with a Pertronix Ignitor replacing the points. The engine has been running great, but last week I started her up for a ride (fired up first turn of the key as usual). After a couple of minutes of waiting to make sure everything was running normal, I went inside to get some water and my fishing license/wallet. I came back out after a few minutes and the engine had stopped. I could not start it again; it turned over fine, looked like gas was getting into the carb throat when I pumped the throttle. I tried spraying some starting fluid and it still did not start, but it was turning over fine. I pulled a plug wire and it did not seem like it there was any spark. All the wires in the ignition system (in a very cursory check) seemed to be connected and in order. I pulled the distributor cap and cranked her and the rotor seemed turning normally. I ordered a new pertronix and coil, but replacing them has made no difference. I checked voltage at the coil with the key on; it was 4.5 at the positive side and 1.2 at the negative side. Back at the ballast resistor, it was 4.5 on the side running to the coil, and 11.2 at the input side. Those voltages seem low to me, could that cause no/low spark enough so that the engine would not even sputter at all? If so, I guess have a bad wire/connection somewhere, where is the most likely place to look? I also threw some more new parts at it, including plug/distributor wires, ballast resistor, distributor cap and rotor, and ignition switch. With a test light to the negative side of the coil, I am getting no flashes when the engine is cranking, removing the tach wire, I still get no flashes. I've checked/cleaned/tightened all the grounds and other electrical connections back on the engine. I'm about at my wit's end with this problem. It seems to me there is a loose wire, but I can't seem to locate a culprit anywhere; I am looking for any and all suggestions.
 
I thought those units require 12 volts to operate and as such instruct you to replace the coil with an internal resistive one and do away with the ballast resistor.
 
Larry, if budget allows, ditch that silly Hall Effect Pertronix kit, and go with a real electronic ignition system.
You do not necessarily need HEI..... and good electronic unit will do.

You'll get a new complete housing, new fresh shaft bushings, new driven gear, new advancing system, new rotor, new cap, new triggering system, etc. and no Hall Effect stuff crammed into this tight circumference as does the Pertronix!

My preference is VR (variable reluctor), although many are having good luck with Photo Eye triggering systems.
 
Many of these HEI's are also EST. If you're OK with EST on this older engine, then it would certainly work.

However, from what I read, the Marine DUI Distributor is apparently not EST.
I like that aspect of it. :cool:

"Performance is also enhanced from the super smooth advance curve tuned into the DUI. A special weight and spring assembly is
hand fitted and dialed-in using a distributor machine for a precise timing curve that will match the specifications of your engine and boat."

 
Thanks all for the advice. Unfortunately, with a new baby on the way an upgrade to a complete electronic ignition is not in the cards. Interesting on wiring the pertronix without a resistor, I know pertronix says on the instructions you can go either with or witout a resistor (depending on the coil). However, I have been running a pertronix ignitor and a MSD blaster 2 coil since 2005, wired as I describe with an external resistor and have had no ignition issues?!? That is why I suspect the way it is wired is not the problem, but I am willing tp try anything (short of multiple hundreds of $$$ into a new ignition system).
 
Larry, can you clarify which system that you have?
You mention:
  • using a Ballast Resistor
  • and that you've been running the Blaster 2 coil

Are you also using the MSD controller?

If so, this may closely ressemble your system.
These will be matched components, so any voltage changes are no doubt done within the MSD system.

Where would your Ballast Resistor be schematically?

ba2a88ea10844973bb17fd81248a5e29.JPG

However, with a typical electronic ignition system, there are two aspects to the voltage requirements.

1.... the voltage required for the triggering unit (be it the Pertronix Hall Effect, Photo Eye or VR triggering).
2.... the voltage required for the primary side of the igntion coil.

These are not always the same.

Mallory's YLM and YLU for example, gives us the choice between both full 12 vdc and resisted voltage for triggering unit power.
The coil's voltage may vary depending on the coil model.
I.E., Ballast Resistor, or no Ballast Resistor.

Back to your MSD unit..... you may have a component that has gone bad.

Give the MSD web site a try.


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No MSD controller; I've been running the Pertronix Ignitor, the MSD coil, and a ballast resistor; wired this way: red wire from pertronix to positive pole of coil, black wire from pertronix to neg side of coil. From negative side of coil also a wire leads to the harness (the tach). From the positive side of the coil, a wire goes back to the low (output) side of the resistor. Again, key to remember is it has run great like this since 2005.
 
I think that we have some Apples/Oranges going on here.

Larry's system is apparently using Pertronix triggering unit, as well as the MSD system.
Kim's Pertronix system if for his Volvo Penta AQ131D engine.


I think that it's best if we keep to the original threads, and keep unlike topics from one another.

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Kim, Larry's system is using the MSD.
Your system is quite simple, and is using the Pertronix type Ignitor (Hot Spark).
In post #9, it appears as though you are comparing these two and perhaps are offering a suggestion based on your Hot Spark unit function.
Look at the MSD schematic in post 7.
If this schematic reflects Larry's system, there is no way that this ressembles your Hot Spark system.

As I see it, Larry is looking for a solution to his particular ignition system issue....., not necessarily a Hot Spark system.
Hence the Apples/Oranges mentioned earlier.

It best serves this forum (and any forum) if/when we keep the topic "thread specific".
If this was a fuel filter issue, then I'd certainly see a reasonable cross over.

Critical?
Well, if that's critical, then I guess I'm being critical.


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Kim, I've found this to be one of the best manored forums that you could possibly find.
I don't want to engage negatively with you.... it serves no one!
Let's keep it civil...... OK?

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Rick, the only MSD component of my set up is the blaster 2 coil, I don't have an MSD controller, so I'm not really set up like the system in post#7. At any rate, I have a new pertronix and a different coil (pertronix flame thrower) on the way and will try wiring them as pertronix suggests and see what happens. I'll bet an imaginary week's salary that ain't it, but I'm hoping I'm wrong!
 
Hey guys. I have enjoyed this Thread. Favor please. Go to my Thread : Kaboodle "Engine Surges at Mid RPM Range" (right near this one) and give me thoughts on my last comment. Also, can you direct me to a good generalized scematic on an eletric ignition system that was put on my 1989 PCM Chevy 305 a couple of years ago. I do not know the model details.
Thanks.
Bill
 
Larry302 said:
Rick, the only MSD component of my set up is the blaster 2 coil, I don't have an MSD controller, so I'm not really set up like the system in post#7. At any rate, I have a new pertronix and a different coil (pertronix flame thrower) on the way and will try wiring them as pertronix suggests and see what happens. I'll bet an imaginary week's salary that ain't it, but I'm hoping I'm wrong!
Click to expand...
Sorry Larry....., My bad!
I read your post #6 as though you had the complete MSD system.
I see now that it's the coil only.

Larry, have you pulled the Hull harness/Engine harness connector apart and looked at these pins/terminals?
Your Ignition circuit will be included in this harness.


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