Let's see why my spark disappeared

[MadScientistMat]

I was finally ready to test out my new radiator setup yesterday, but only made it a few hundred feet before the engine stalled and would not restart. I got to work sniffing out the problem. Literally, as I could smell dead electronics. Didn't take long:

I've had this MSD 6A for nearly 20 years, but it doesn't have much run time on it. Let's open it up...

And unbolt the circuit board - this doesn't look good.

I think this is the circuit that feeds the high voltage transformer. Stay tuned; I'm going to see if I can come up with more details about what might have killed this box.

 

[67Dart273]

Where was it stored? Water? Humidity? remember part of that is a 12V to high voltage inverter. I don't know what the output is, likely above 150V and approaching 300. Humidity in a transformer could do that, along with water/ corrosion on other parts

 

[Plymouth 65]

That MSD box is cooked! 65

 

[Desoto291hemi]

Yep,,,,Age and corrosion got that one .
Electronic units don’t respond well to corrosion build up on them .

Tommy

 

[MadScientistMat]

The car was kept outside a lot and I know under the hood isn't ideal. But with the board being in the lid and heavily conformal coated, I thought I could get away with it.

 

[Desoto291hemi]

That’s fine,,,you didn’t do wrong .
It’s just normal condensation from heat cycles,,,and the weather .
It will still cause corrosion inside electronic equipment,,,just takes a while .

Tommy

 

[Inertia]

The car was kept outside a lot and I know under the hood isn't ideal. But with the board being in the lid and heavily conformal coated, I thought I could get away with it.

You gonna repair it, you seem to have the aptitude .?

 

[gzig5]

It blows my mind that they don't conformal coat these boards when they fully understand the environmental conditions they will be subjected to. For something that size it would add about $2-$3 max to the cost of the PCBA. Reliability in hard conditions would go up significantly.

 

[MadScientistMat]

There's some pretty thick conformal coating on the board. I might try repairing it depending on the extent of the damage, but I'll bypass it for now.

 

[TT5.9mag]

I can smell that from here. Once you smell burnt electronics, you can never un smell them.

 

[OttawaCharger]

once you let the magic smoke out, she don't work no more.

 

[Lefty71]

You welded on the car while that box was still installed in it???

 

[MadScientistMat]

I did leave the box in place for a few welding tasks, but that was long ago, the battery was disconnected, and I was very careful to keep the ground clamp as close to the weld as possible.

 

[Lefty71]

and I was very careful

So was I lol....but thats how i knew.

I sent mine back to MSD and its like new now for $100.

 

[toolmanmike]

She ate her pigs. I could say "typical MSD" but I won't.

 

[Bewy]

The rear side of the printed cct board in post #1 looks like there may be an overheated solder joint, just to the right side of the transformer core. Maybe a dry joint that got worse? Perhaps re-soldering may fix it.

 

[MadScientistMat]

If something I did killed it, right now I am more likely to suspect one of the earlier failed prototype voltage regulators. Those took a couple tries to get right.

At this point, besides a closer examination of the damage, here are the plans for the car:

1. Bypass the MSD box to get the car running.
2. See if I can fix the box myself - but don't trust it. If it goes back on the car, it will have connectors added so I can easily bypass it.
3. Whether fixing the MSD box succeeds or not, eventually I plan to set up a crank fired coil per plug ignition.

 

[TT5.9mag]

She ate her pigs. I could say "typical MSD" but I won't.

How many MSD boxes have you personally had leave you stranded?

 

[67Dart273]

Do you have the car running again? Just check the running/ charging voltage at the battery. I doubt "a little" over voltage killed it. if the regulator has failed and cause full output charging, then, maybe.

 

[toolmanmike]

How many MSD boxes have you personally had leave you stranded?

 

[TT5.9mag]

What’s funny? That was a serious question.

 

[toolmanmike]

What’s funny? That was a serious question.

Let's put it this way, I have no need for a MSD.

 

[TT5.9mag]

Let's put it this way, I have no need for a MSD.

That wasn’t the question. How many have YOU had leave you stranded? You started to bash the product ……

I could say "typical MSD" but I won't.

And a lot of guys do the same thing with comp, MSD, etc. but have no practical working relationship with said product. They’re (you’re) just repeating what you’ve seen or heard on the interwebs. So I figured I’d ask. And I got the response I could have predicted.

 

[toolmanmike]

That wasn’t the question. How many have YOU had leave you stranded? You started to bash the product ……



And a lot of guys do the same thing with comp, MSD, etc. but have no practical working relationship with said product. They’re (you’re) just repeating what you’ve seen or heard on the interwebs. So I figured I’d ask. And I got the response I could have predicted.

Through the years, here and on FBBO, there have been an awful lot of failure threads and posts. Also, it seems that every time I am at the drag strip, there is an announcement or two asking for a 6AL box or what ever. There may be a million of them out there but there seems to be a lot of failures. No, I've never owned one. If you use them with good results, that's good for you.

 

[TT5.9mag]

Through the years, here and on FABO, there have been an awful lot of failure threads and posts. Also, it seems that every time I am at the drag strip, there is an announcement or two asking for a 6AL box or what ever. There may be a million of them out there but there seems to be a lot of failures. No, I've never owned one. If you use them with good results, that's good for you.

Excellent. Thanks for the honesty. Now please stop pushing the banter of “typical MSD” until you have a problem with one. And take notice next time you hear of one leaving somebody stranded, at their wiring, installation, and/or location and you’ll begin to see why some dumbasses can kill anything.