I need to do some research but I think I know what your problem is.
First, what is your ignition module mounted to? Sheet metal?
Second, where is it mounted? Front of dash firewall? In the doghouse?
Third, what exactly are you doing when you mount a new one? (Step by step.)
BRB, once I check some things out to be sure.
1970 Explorer Class A on a 1969 Dodge M300 chassis with 318 cu. in. (split year)
1972 Executive Class A on a Dodge M375 chassis with 413 cu. in.
1973 Explorer Class A on a Dodge RM350 (R4) chassis with 318 engine & tranny from 1970 Explorer Class A
Good article on Mopar electronic ignition.
More applicable info from a question/answer in another forum.
A lengthy, detailed set of info, encompa........ including lean burn and other issues.
A large collection of good reference information.
Lets see... disconnect wires, unscrew from firewall, screw in new module... hunt for the ^%$#^$ screw I drop 3-4 times trying to line it up behind the brake stuff, reconnect the wires. Drive off...
Read the links above ... five with four is good, and OEM. Five with two is not, and won't work. Four with two is OEM but four with four will also work.
You're seeing an example of my 'high-speed, low-drag' research technique ... spinning through tons of info while picking out relevant information ... and hopefully hitting on one or two clear, complete, and concise answers.
Yesterday and overnight (while sleeping), the back of my mind kept nagging me about a voltage regulator mounting issue. (Dodge voltage regulators need a good, solid ground -- negative -- connection to work properly.)
My mind seem to be trying to tell me there's a connection between how voltage regulators and ignition modules are mounted. I knew it wasn't a ground/negative connection issue for the ignition module. (Dodge ignition modules get their ground/negative connection from a dedicated wire rather than what they're mounted on ... versus the metal body common ground for voltage regulators.) So, I kept dismissing the intrusive thought.
(Why do I keep hammering on about negative/ground issues? Because, it's the cause of so many frigging problems!)
This morning, the connection hit me ... heat! I vaguely ... kinda ... recalled something I read decades ago.
Dodge ignition modules need to be mounted to large (area) pieces of sheet metal, which serves as a heat sink -- to dissipate heat away from the module. I kinda recalled reading about using heat sink compound between the ignition module and what it's mounted on to help dissipate heat. (Heat sink compound is a grease-like substance that conducts heat well.)
So, the "protectant on the back has leaked out everywhere" is very likely heat sink compound, added by someone to make sure things continued to work. (A rare example of a previous owner -- or mechanic -- actually knowing what they're doing.)
Excessive heat always causes electronics to fail. That's why your computer has a big noisy fan ... and why I fried two laptop motherboards ... and why -- at Leeann's recommendation -- I've added software for overdriving the fans in my current computer.
The sealant on the back side of ignition modules SHOULDN'T melt. (It takes a heat gun and several hundred degrees F to actually melt it.) If it is melted, then you definitely have a heat problem, either from the module itself or where it's located. (Or, the manufacturer used substandard sealant, in the case of aftermarket modules.)
General consensus across everything I've spun through this morning is aftermarket modules are ****. Especially if they're manufactured overseas and particularly in Asia. The consensus is also you should only use genuine MOPAR modules ... and the older the better. (Dodge, like many others, has been cutting costs -- and corners -- lately ... A727 versus A518 is an example.)
So, get -- and use -- some heat sink compound. It will be hard to find. Radio Shack would have been a good source, if the web and Sears hadn't killed them off. So, look for an electronic parts store (local or online). If the store/website doesn't specialize in electronic parts (versus televisions, DVD players, stereos, and other doodads), look elsewhere.
RTV silicone, and similar 'heat' products, won't work. (They resist heat rather than conducting it.) It has to be heat sink compound, made specifically to conduct heat.
And, stick with your old, rusty, corroded, ugly, original, genuine MOPAR module.
DanStokes on a www.bangshift.com forum. wrote:
Joe - you guys probably have heat sink compound lying around (ask the electronics guys). Coat the bottom of the module before you bolt it to the plate and it'll conduct the heat MUCH better to the plate. We used the stuff (ours came from Omega) to get thermocouples to read the temp of a fuel tank as we heated it.
Joe - you guys probably have heat sink compound lying around (ask the electronics guys). Coat the bottom of the module before you bolt it to the plate and it'll conduct the heat MUCH better to the plate. We used the stuff (ours came from Omega) to get thermocouples to read the temp of a fuel tank as we heated it.
Afterthought: Some people use a custom-made aluminum or copper heat sink. (Copper conducts heat better but aluminum is almost as good ... and cheaper.) This specially made heat sink is a bridge-like, with two legs to raise the module up off what's it's mounted to. This allows airflow under the 'bridge' to draw more heat away. (The metal legs also conduct heat to what the module was originally mounted to.)
I can draw and post a 'picture' if you're interested.
![[image]](http://i64.tinypic.com/11rxjpw.jpg)
Looking at your picture, I'd say it's probably heat sink compound.
The sealant on the back of the module would be a thicker, gooier, solidified mess if that had melted. (I've seen pictures online of someone melting and removing the sealant ... to do something I wouldn't recommend.)
Oh, don't try to clean up the appearance of your module ... paint and a lot of other 'appearance improvements' would just make heat issues worse. (I might be able to very carefully do an appearance restoration. But you'd have to send the module to me and I'd have to charge for the service. (Doing so is one of the businesses I run.)
That is the linkage between the brake master cylinder and brake pedal. Jamming or seizing would 'not be a good thing.'