1. turbofiat124

    turbofiat124 Premium Member Forum Donor

    Been awhile since I've been on here. So here is my latest attempt at my DYI electronic ignition system:



    Now I got a new issue, the car runs great but is a sometimes hard to start. Meaning I can crank and yet at times I seem to have no spark when cranking.

    This battery is almost 10 years old. I've decided when this battery dies I'm going to convert it to a 12 volt system to do away with all the work arounds I've done just to run certain circuits that have to run on 12 volts. I've got most of what I need.

    Right now I have a battery charger hooked up and so far the engine will fire within 1 second. The last several times I've cranked it over.

    I'm wondering if the battery is starting to loose it's CCAs it doesn't have enough balls to spin the engine over fast enough.

    It doesn't sound like it's struggling to turn over though.

    Since I've done away with the retard mechanism and run a fixed 4mm BTDC, like the EBZA system, I've heard the purpose of the retard system using points is to make the engine easier to start like with a weak battery.

    I'm not sure what's up. The engine runs fine otherwise. I had it up to 110 kph with no missfires. Pull into my garage, shut the engine off and it won't start until I hook a battery charger to it.

    When I check for spark using a timing light I don't seem to have any spark unless I hook a battery charger to the battery.
  2. Andrew353w

    Andrew353w Puttering Along

    I'd suggest doing a "capacitance test" on your battery. This tests the strength of it and shows how much "oomph" has when it's starting the car. Any decent motor accessory shop or garage would do this and advise you what condition your battery is in. As a guide, a 6 volt battery should still deliver 4+ volts when cranking the engine. Anything less than this means the engine won't be cranked quickly enough to start and there won't be enough in reserve to work the ignition circuit.

    I'd be sceptical about converting the car to 12 volts. It's not that easy a conversion and I'd advise keeping the car on 6 volts, but do regular maintenance on the electrics to keep them up to standard.

    Happy to explain more if needed, or visit (if you're not too far away from north London....)
  3. turbofiat124

    turbofiat124 Premium Member Forum Donor

    So far the battery is holding at 6.4 volts and the engine fires up within one second. I kept a trickle charger on it over the winter. But took it off a couple of weeks ago.

    I can tell that the motor spins over faster after recharging the battery.

    Sounds logical if the starter is pulling too much power not allowing the ignition to fire.
  4. Andrew353w

    Andrew353w Puttering Along

    I'd be interested to know what the voltage reads on your meter WHEN THE STARTER IS OPERATING if you're able to read it and operate the starter simultaneously! This should be about 4 to 4.5 volts, as your system is a 6 volt one.
  5. A Spooky Ghost

    A Spooky Ghost Loyal Comrade

    I know electronic ignitions are sensitive to low voltage while cranking. Usually if too low u get no spark. "Either has spark, or doesn't". Your batt just might be slipping... Maybe check the volts while running with a multi-meter meter.

    Also maybe your new ignition is losing ground/ shorting out?
  6. turbofiat124

    turbofiat124 Premium Member Forum Donor

    I have had issues with one of the modules loosing ground due to that heat sink paste but in this case both modules don't fire and checked for continuity against the PCB board and ignition housing.

    I could have a huge voltage drop when cranking because my radio lost its presets and the clock. And I added a step up converter to the memory wire just to prevent this .

    I'm going to take some voltage readings, battery, battery when cranking, could and modules. Gotta go to work so will do that later.
  7. turbofiat124

    turbofiat124 Premium Member Forum Donor

    I've determined the modules are getting too hot. If the car sits for two hours it fires right up. Perhaps the material I'm using to mount the modules is acting like a heat sink.

    Before I was using Lexan and aluminum tape.

    I have not road tested the car but found these 12 volt modules will fire on 6-7 volts. The theory is excess voltage causes heat. So if you can get by with less voltage the modules should run cooler.

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