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Discussion Starter · #1 ·
has anyone replaced the transistors inside the ignitor on one of these? I have a few ordered, going to see if that fixes my cdi problem when they come in
 

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has anyone replaced the transistors inside the ignitor on one of these? I have a few ordered, going to see if that fixes my cdi problem when they come in
To my knowledge, nobody has done on-board repairs of the ignitor. Anything you can share as you dive in would be welcomed.
 

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Discussion Starter · #3 ·
To my knowledge, nobody has done on-board repairs of the ignitor. Anything you can share as you dive in would be welcomed.
there is a hole burnt into the top of one of the transistors fir the coils inside my cdi, I'm hoping ican just solder a new one in, it has 3 points that solder into the board, than is screwed into a heat sink. im not electrically inclined, but I'd say it's the transistor that makes the little spark a big spark. lol
 

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The transistors basically just act as traffic cops and allows current to flow in only one direction. I haven’t taken these apart to see but the spark is powered by capacitors, these build up voltage and discharge at a certain point, hence the name “CDI” or “capacitive discharge ignition” curious as to how much it costs to just replace the transistors. You can find junction boxes at a decent price on eBay.
 

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Discussion Starter · #5 ·
well it is smoking when iturn my engine over, and that's no good. lol
 

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There’s a saying in the electronics world. And that’s “once you let out the magic smoke the device is probably shot”. I wouldn’t discourage you from trying to change single components but wouldn’t be surprised if something else or the board itself is fried from the surge.
 

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Discussion Starter · #7 ·
There’s a saying in the electronics world. And that’s “once you let out the magic smoke the device is probably shot”. I wouldn’t discourage you from trying to change single components but wouldn’t be surprised if something else or the board itself is fried from the surge.
eh, well I'll mess with it until i find a cheap ignitor somewhere, lol. the transistors are like 2 bucks on Ebay. the worst that can happen is probably me burning myself with a soldering iron
 

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Discussion Starter · #8 ·
there were also a couple of burnt pathways on the back of the board, and a couple of cold solders, so i cleaned it up and soldered the broken paths and connections. if a capacitor blew, idon't think I'd even be able to find it. lol
 

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Discussion Starter · #9 ·
and i thought transistors were amplifiers, and the diodes were part of the relay in the jb?
 

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I found an aftermarket ignition controller that is programmable and otherwise plug-and-play with the Vulcan Ignitor. You can read all about my installation process here. I can set up a program for the stock timing if you'd like.

I would check for shorted wiring from the ignitor, and shorted ignition coils. If the transistor blew out, there has to be a reason. You might succeed in your repairs, only to have it blow out again.

I don't think the OEM ignitor is a CDI type. I did a lot of playing around with the ignition system, and it looks more like an inductive ignition system. The coils are connected on one side to the battery (through some on/off switches). The ignitor uses a transistor to connect the other end of the coil to ground. This causes current to flow through the coil. The manual says the coils are between 1.8 and 2 ohms, and Current = Voltage / Resistance (ohms). So current should be around 6 amps. I measured the current while running and I saw about 6-7 amps. Since the coil is an inductor (inductors resist a change in current), the current doesn't instantly go to 6-7 amps, but ramps up rather slowly (see the pictures I posted). When the transistor turns off, the current should go instantly to 0. However, since inductors resist a change in current, it causes the voltage in the coil to spike really high. This voltage spike becomes the spark.

The transistor is an amplifier. There is a small signal coming off the pickup coil that sets when the spark should happen. This signal is not strong enough to charge the ignition coil. So instead, the signal is run to the transistor, which amplifies it to something strong enough to run the ignition coil
 

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i don't know wtf you just said kid... but i like you. lol
Hahahahahahahahahahahaha

The most important part was the aftermarket ignition controller I found that's plug and play.
 

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that is the transistor that is blown. or damaged anyways
I would check for shorted wiring from the ignitor, and shorted ignition coils. If the transistor blew out, there has to be a reason. You might succeed in your repairs, only to have it blow out again.
 

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I don't think the OEM ignitor is a CDI type. I did a lot of playing around with the ignition system, and it looks more like an inductive ignition system.
^^^^^^ Yes. This. ^^^^^^

The transistor package you are showing with a hole in it, is what's called a darlington (transitor) pair. A control chip that times the spark triggers the transistor like a switch to ground one side of the primary windings in the ignition coil. EMF from the current surge in the primary, induces the secondary like a transformer; pushing a dense collection of electrons toward the spark plug gap, and jumping across to ground, creating an arc (spark). I think.

The failure mode of the transistor pair could have possibly fed power back to the chip. What components were at each end of the burned traces ? That might tell you what other components were exposed to possible damage. Good luck.
 

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Discussion Starter · #18 ·
the burnt traces were just around the transistors, will be Monday before iget the replacement now =[
 

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Discussion Starter · #19 ·
you guys happen to know where icould find a pinout for the 6pin connector?
 

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you guys happen to know where icould find a pinout for the 6pin connector?
See if the diagram in post #8 is any help:

 
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