Help Me Repair My Mallopry Unilite Ignition Module, Please.

[19Fordy]

I am trying to repair my Mallory Unilite Electronic Module but am stumped.
The part I need to replace is the little black (transistor?) called the IGBT (Part # IRGS14C40L) that the pencil below is pointing to.

I thought it would be a simple matter of unsoldering the old transistor and installing the new one. I found that using a soldering gun to un-solder the old piece did not work. The circuit board is on top of an aluminum base and the "wire" in the circuit board is not really wire. It just appears as a white markings.

I then tried to use my dremel to grind away the old resistor but when I hit the copper layer you see in the photo I stopped. Also the 2 connecting points on the circuit board for the resistor just fell off. There was no solder that I could see.

I am not an electronics person. Is this a new kind of circuit board manufacture? What can I do to attach the new transistor to the circuit board? The base of the original transistor under the copper is still attached to the board. Is it a special conductive glue that I need to use instead of conventional soldering?

Being able to install my new transistor would be much, much cheaper than buying a new Mallory module. There must be a way of doing this repair. Your thoughts are appreciated. Thanks, JIM

[tubman]

If nobody gets back to you in a reasonable length of time, I'll ask my neighbor who knows about stuff like this. I don't know much. but from hanging around with him, I think this may not be a simple straight forward component replacement. Perhaps some one on here can prove me wrong.

[4t8v8]

That is an insulated gate bipolar transistor of the MOS type. The manufacturer of the board made it almost impossible to replace successfully. When you are handling it be sure to wear a grounding strap on your wrist as they are very sensitive to static electricity. These units fail very rarely on their own. Another component on the board probably caused it's failure.

[TJ]

You are going to have to buy the module. You do need to know why it failed. Those modules are sensitive to electrical spikes ,so hopefully you can check to find out if that is what caused the failure. Mallory made a filter for the Unilite that stopped spikes, but I don't know if it still available. Check with Summit Racing. If it's still available they would probably have it.

[BillM]

I assume that is a new replacement IGBT in the third picture? The tab opposite the two pins is a heat sink that is meant to be soldered to the board; that looks like what you have been grinding on. You can Google "SMD soldering" or "SMD repair" to get some idea of what it takes to work on surface mount boards like you have. Lots of luck.

[19Fordy]

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Thank you all for the very informative info. Wow! I am definitely in over my head when it comes to fixing my module. Lots of specialized equipment and knowledge required. I did find a good video on SMD soldering. Pretty slick but way above my pay grade. However, I did learn something new re soldering circuit boards..
https://www.youtube.com/watch?v=z7Tu8NXu5UA

[tubman]

Points work better, anyway.

[Jay in Mass]

Looks like something that can't be fixed on the side of the road.

[hotrodcbx]

Personally, even as a retired electronic engineer, I would not bother with a repair. These units are available from numerous sources like Summit racing for about $60.00. I have used these units in both my 33 and 34 Fords using Chev Unilite distributors (machine work rqd. and recurving needed) and have not had a failure. Many people install these units and do not install the resister necessary to reduce the voltage which will lead to premature failure.

[BUBBAS IGNITION]

Originally Posted by hotrodcbx

Personally, even as a retired electronic engineer, I would not bother with a repair. These units are available from numerous sources like Summit racing for about $60.00. I have used these units in both my 33 and 34 Fords using Chev Unilite distributors (machine work rqd. and recurving needed) and have not had a failure. Many people install these units and do not install the resister necessary to reduce the voltage which will lead to premature failure.

More like $113

https://www.summitracing.com/parts/maa-605

[BUBBAS IGNITION]

Originally Posted by 19Fordy

Thank you all for the very informative info. Wow! I am definitely in over my head when it comes to fixing my module. Lots of specialized equipment and knowledge required. I did find a good video on SMD soldering. Pretty slick but way above my pay grade. However, I did learn something new re soldering circuit boards..
https://www.youtube.com/watch?v=z7Tu8NXu5UA

I will look in my junk box , i may have a couple you can have ????

[tubman]

Originally Posted by BUBBAS IGNITION

I will look in my junk box , i may have a couple you can have ????

This alone tells a tale.

[philipswanson]

You can buy generic modules on E Bay for sometimes less than half price.

[34PKUP]

Originally Posted by philipswanson

You can buy generic modules on E Bay for sometimes less than half price.

How about posting a link to these "generic modules" that are a direct replacement for the Unilite modules

[BUBBAS IGNITION]

Direct link to china but i ordered one. Could very well work just as good as the factory unit (also made overseas) ???????

https://www.ebay.com/itm/E-Spark-and...ZaE~4G&vxp=mtr

But understand if it works i want $120 for it .....

[51 MERC-CT]

Originally Posted by BUBBAS IGNITION

Direct link to china but i ordered one. Could very well work just as good as the factory unit (also made overseas) ???????

https://www.ebay.com/itm/E-Spark-and...ZaE~4G&vxp=mtr

But understand if it works i want $120 for it .....

If I had not already replaced my Unilte with a Pertronix conversion I may have ordered one.

[flatheadmurre]

When we order stuff from china...first batches is dissasembled and you can find the most funny stuff.
Reused components and not so eqvivalent semiconductor swaps was real usual to find...paying a bit more to the chinese and you get descent quality products.
Biggest problem is the traders in the middle not knowing or caring about the product one bit.
Another issue is if you don´t buy from the manufacturer...and the module you buy now works just fine...the trader found a cheaper supplier next time with a product that looks identical...only cheaper..and worthless.
But a $22 gamble isn´t to bad if you don´t get stranded in the wrong place...

[tubman]

Let's see. Some are suggesting that the O/P purchase a Chinese knock-off part from an unknown source on eBay to try to repair his aftermarket electronic ignition system that has a known record of failures? How do I sell that short?

[rotorwrench]

My wife ran a solder wave machine at her workplace for a while but it was only part of the process. The SMT machine operator plugged all the stuff on the boards then it was run through the solder wave to fix all the stuff to the boards. My wife works in the coating department now where they coat the boards with special sealants to prevent corrosion and moisture shorting. The boards are for the soda dispensing machines that the company she works for produces.

That little Unilite board may also have one of those silicon coatings on it making it difficult to repair. It would likely be easier to fabricate a board from scratch than try to repair that one.

[itslow]

Buy a new module. Trying to complete the component replacement on the board you have now will only open up additional headaches and potential sources of failure.