Ignition module leak?

When I was in the Army, working on electronics, most of the old tactical systems had their Circuit Boards coated with a clear-ish substance.  I had to use a heat gun to soften and peal away the spot on the board where I had to replace a component or make a trace repair.

You may want to find/make a Heat Sink to mount this device to..

How is the module mounted?

Would it be beneficial if I allowed more air flow underneath it?

Ok guys & girls back about a month or so ago when my son was here and we were bleeding the brakes he pointed out to me the same thing. The module leaked goo out and down the fender liner.

Now for all you that say wrong coil, I call bs on and the same if you were to say the key was left on bs.
I say this because the truck has not been run other than in & out of the garage, maybe up to temp to test the temp gauge so not vary long run times.

The coil has been on that motor before I bought the truck all be it with a different IGN box as this one came on the parts truck inner fender and it ran with a different motor.
So I cant see it wrong coil and it never ran long enough.
Oh I don't have a hood on the truck so cant trap any engine heat.

As for leaving the key on, the battery cable is removed each time the motor is turned off because the head light switch is still pulled out from when I removed the knob and I don't want to install the knob yet as I have other dash work to be done yet.

Now I can tell you it gets really hot in the garage. I would say many days it had to be over 100*f with it closed up as I have seen it mid 90's with everything open and a fan going.

So I call the heat is why it leaked. I will run it till it stops / gives me issues and then will use the one that came with the truck.
Dave ----

I think the modules "run" from heat, but that heat can come from different sources.  In David's case it came from too much current due to the wrong coil being used.  But in my case, which is similar to yours, it appears to be a hot environment.  The attic to my shop never gets over 100 degrees, but the module sure ran while up there.

Vinny, now that you mention it, I too recall that coating on circuit boards. It was called conformal coating if I recall correctly and the purpose was environmental protection. It is quite a bit different from what modules were sealed up with, which was some type of epoxy and was referred to as potting compound. I suppose one could use enough of the conformal coating to fill a box, but I recall it being used primarily on SMD boards and it came in a spray can. My experience was primarily in radio communications. Way back, there was also a paintable type of product called Glyptol. I recall using that on high power AM/FM commercial broadcast equipment back in the 70's.

Anyways, I still was surprised to see the bottom of that module. Clearly, the compound did break down, liquefy and reharden on the inner fender. I agree with Dave that the ignition coil was not the culprit here. The very nature of what the ignition module has to do will generate heat. That is why I am surprised that the manufacturer of the ignition module would use a compound that would melt. Looks to be an original piece as well, so I can't even say they don't make 'em like they used to!

I forgot to say the other box I will use if / when the leaky one fails has been  outside on the fender and it has not leaked.

I cant remember if either one is a true MC unit or aftermarket but am sure both have the blue retainer.
I will have to check that out next time out in the garage.
Dave ----

Gary, I don’t know what the melting point of that resin is, but it can’t be ~too sensitive. I took my ‘81 to BHC this August and the ambient temp was 122*F, plus whatever the engine bay and coil current added. I am really wondering if there are electrical components inside that leak a chemical that interacts with the resin?

There are probably electrolytic capacitors in there, and their fluid is very caustic and might cause the epoxy to melt.  

Years ago I had an inverter that took DC from a set of batteries and turned it into AC for the computers.  It had 3 large electrolytic caps, each about the size of a 2 liter Coke bottle.  The center one blew and took out the other two.  Everything inside the cabinet, which was the size of a large refrigerator, was ruined - and the paint ran down the sides of the cabinet like paint thinner had been sprayed on it.

https://www.ebay.com/p/300x140x20mm-Aluminum-Heat-Sink-Heatsink-for-High-Power-LED-Amplifier-Transistor/23003357190?iid=292239720229&_trkparms=aid%3D222007%26algo%3DSIM.MBE%26ao%3D1%26asc%3D20131231084308%26meid%3D8a9cf6ad755d4d75be3f1f2dab17899f%26pid%3D100010%26rk%3D6%26rkt%3D12%26sd%3D263586792036%26itm%3D292239720229&_trksid=p2047675.c100010.m2109

Or, tap into your A/C system; http://www.tran-tec.com/liquid-cooled-heat-sinks.php

A quick Google search shows that Duraspark module melting issue has come up before. There's a picture at the bottom of this thread with the same green goo, as well as others saying they've melted them.

https://www.ford-trucks.com/forums/1221215-any-tips-preventing-a-melted-duraspark-ignition-module-2.html

Bronco's...

http://classicbroncos.com/forums/showthread.php?t=241854

Mustangs...

http://vb.foureyedpride.com/showthread.php?124077-5-0-ignition-control-module-epoxy-melting

Interesting in the thread below the second comment regarding the voltage.

https://www.fordmuscleforums.com/garage/462483-why-do-i-keep-burning-out-ignition-box.html

This all reminds me that I need to clean up the spare 86 DSII box I purchased and throw it behind the seat for a spare...lol.

neoniacin wrote

How is the module mounted?

Would it be beneficial if I allowed more air flow underneath it?

That probably wouldn't hurt (or to use a heat sink like Vinny is suggesting). There is a pic of a lifted box in one of threads above. For the few cents is costs, probably not a bad idea. The plastic fender liner isn't dissipating any heat.



There was a comment in one of the threads linked above where the guy said he was melting a module every six months until he moved it into the cab somewhere. After that, no more issues. In his particular case, it sounds like the engine bay heat was killing it, OR there was a wiring issue that he inadvertently fixed when he ran new wires into the cab.

Interesting stuff none the less.

Ford F834 wrote

I took my ‘81 to BHC this August and the ambient temp was 122*F, plus whatever the engine bay and coil current added.

Jon, I swear to god even reading that makes me start to perspire...

I've only been to AZ a few times, and the last trip when I did Camelback Mountain it was only around 110-111*F. However, I've spent a little bit of time in the middle east, and have experienced 122*F. My pale Canadian skin likes it much better when it's only about 75 degrees.

Spacing the module up may help.  But you can also gain a bit of cooling by stacking another module above that one this way.  It doesn't dramatically help as the contact area of the nuts and bolts is relatively small, but at least the backup unit is ready to go when/if the time comes.

Rembrant wrote

Jon, I swear to god even reading that makes me start to perspire...

I've only been to AZ a few times, and the last trip when I did Camelback Mountain it was only around 110-111*F. However, I've spent a little bit of time in the middle east, and have experienced 122*F. My pale Canadian skin likes it much better when it's only about 75 degrees.

Unfortunately I never got my AC install done, so yeah... I couldn’t wait to get back over the mountain to Golden Valley where it was only 107*F ha ha. I had a cooler full of ice water and rags. I would not have gone except we found a deal on some water haul tanks that I didn’t want to miss out on. The truck did fine though, no overheating even on the long climb out of BHC. And no melted DSII 👍

Edit: and now it’s our turn to enjoy the 70’s*F 🙂

I've used a CRC electrical contact cleaner pretty successfully on connectors like that.  That and a nylon brush.

I never have melted a module, but I had problems over the summer where my box would stop working when the temperature outside neared triple digits.
I replaced the box, and it happened less often but still was likely to kill the motor if I tried to go up a big hill. I finally put some washers between the box and the inner fender to give it airflow, and that fixed the problem completely.
It has never had that problem again, and it fixed it immediately. I would highly recommend it to everyone even if your box hasn't overheated yet.

It goes to show, most of my biggest and most important fixes I do on this truck are either free or ridiculously cheap -- and easy. It likes to teach me lessons about working with what I've got.

This isn't only parts but also some less common tools I always keep with me...

Make sure you have jumper cables, not just for jump starting, but in case something electrical stops working.

I had to use them in the middle of a long road trip because I pulled into a gas station and the truck wouldn't turn back on! No dash lights, no starter, nothing. I jumped the battery power straight to the starter and got the truck to start right up and get me to the parts store. Turned out to be a shoddy connection from the battery to the starter solenoid -- truck could only run off the alternator till I fixed it.

Other than that, I keep some bailing wire in case I need to replace a cotter pin (still have wire in my clutch linkage instead of pins -- I really should replace that) and wire also helps to hang up exhaust or anything hangy if it gets knocked down partially. You could wire your choke in position if that goes out and you have to drive somewhere... or you could use the little wire to poke an obstruction out of the carburetor or clean up an electrical connector on the side of the road. Make sure you have wire cutters too -- otherwise you won't be able to do much with your wire!

Keep channel locks in case you need to remove a stripped nut. I had to use channel locks on one of my fuel line nuts because it was unbelievably rounded off. Ended up converting to a soft fuel line with an inline filter.

It's always a good idea to keep extra bulbs too -- whether they're the little 194 interior bulbs or the exterior ones. Might even help to have a sealed beam lamp somewhere if you have room.

I keep a nice little rubber mallet under the seat. Haven't needed it much but it's sure a whole lot better than using your hand to give something a good whack if you need to mess with a drum brake or a u-joint or the like. My friend borrowed it once when his Ranger blew a u-joint, and it came in handy that day for sure!

Last but not least I always swear by zip ties. A pack of 100 is super cheap and they'll fit anywhere in the truck. You can use them to keep wires or hoses out of the way or attach something back together if it's not load-bearing. I keep on using them, usually for "temporary" fixes, but I would not go anywhere without a pack or two under the seat.

THERMAL CONDUCTIVITY = k = W/(m k)
       
MATERIAL @25C

Diamond 1000
Silver  429
Copper  401
Gold          310
Lithium  301
Beryllium  218
Aluminium   205
Tungsten  174
Graphite  168
Pinchbeck  159
Magnesium  156
AIR          000.025

Maybe 0.025 W/m.K. is all that is needed to keep the failing boxes at bay..
Time will tell...