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Discussion Starter · #1 ·
When I install my newfangled aftermarket ignition system, I want to put the computer somewhere where it will be dry and safe. I'm thinking along the lines of either a tuperware container, or an old ammo can mounted underhood somewhere...and then just silicone the holes for the wires and mounting bolts... But what about heat? Will these computers build a lot of heat? Is there any problem with an air/water tight box like I'm thinking? Oh, and what do I need to do to waterproof the distributor? Silicone it on and drill out a vent line?

P.S. A side question...The previous owner of my jeep took the liberty of installing gauges in the dash immediately to the right of the speedo...and they stick into the space behind the dash, apparently enough to make him remove the duct that directs air up to the defroster. Now, with the bestop on it, defrost is something I'd like to have. Any ideas on how to direct the air up there with my limited space???

Measure once, cut twice...or is that the other way around?
 

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You didn't say what ignition system you were using.
If it's a GM style HEI, there is no way to water proof them. You can make them water resistant by using dielectric lube in the plug wire boots, and using a little silicone around the distributor cap base, but it's going to leak around the coil no matter what.
If you don't vent the distributor cap in some manner (especially if you got talked into one of those 'Mega' coils for the cap), you are going to have cross fire and ground fire problems because of the ionized air (ozone) that builds up when high electrical energies discharge.
Keep your eyes open for what looks like pencil lead dust and pencil marks on the rotor, and inside the cap. (carbon tracks) This is a bad thing, and a symptom of too big of a coil discharge for the design of the rest of the ignition system. So is red dust under the rotor, and on the distributor shaft and weights.

If you upgraded to a DuraSpark system, then the module is already water tight. Don't forget to squirt the Dura Spark module connectors full of dielectric grease before plugging them into each other.
The only changes I would make is to drill the vent hole on the bottom of the Motorcraft distributor and install a nipple for a vacuum line to the air cleaner. If you have the Motorcraft distributor, and upgraded to the two piece cap, then the cap has a vent already on it. Don't use metal, but glue or epoxy a plastic hose or nipple on it for a fresh air source above the water line. Use silicone to seal the cap base to the housing, and the cap top has a groove in it that a little dielectric grease seals in a snap. Don't forget to lube the plug wire boots also.

If you got an MSD box, install it inside the jeep where it can get fresh air, or second choice is to install it in front of the radiator opening up high. It's best if you don't submerge the MSD boxes, and a reasonable amount of air flow will insure a long life for the module. Do the distributor as described above. (I'm assuming you didn't use a GM HEI with a MSD in the 304/360 set up)

Both MSD and DuraSpark need open air to cool themselves.

As far as your duct work goes, use poster board cardboard, and make a duct the way you need it. Take that template to one of the local shops that say, bend duct work for heating and cooling systems, and have them make you one. We have done that a bunch of times, and it's not expensive at all, and the results are wonderful!

Hope this helped, Aaron.

So many cats, so few recipes...
 
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Discussion Starter · #3 ·
OK Rush -
Just where oh where do you get 'dilectric grease'? Inquiring minds want to know. Seriously, this term has been bandied about for quite awhile and some of us simply don't have a clue and you all are telling us the good things for it and I for one believe you and will follow your advice but -----------
TIA
sln

 

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S. L. Newcomb,... you do get around...
I think you just tagged one of my other posts...

'Dielectric grease' is that little package of vaseline looking grease that comes with most plug wire kits, distributor rebuild kits, ect.
Any auto parts store, (even the local auto-jerk discount stores will have it if you can get the head scratcher behind the counter to look for it...) or you can buy large tubes of it at electrical contractors discount houses.

Permatex sells the dielectric grease in a 0.33 oz. tube under part number 67V that is available in nearly all parts stores for about $2..
Permatex also sells a pre packaged 'Tune Up Kit' with the 0.33 oz. tube of grease, and a 0.24 oz. package of 'anti-seize' for the spark plug threads under the part number 26984, for about $4.
(Can you tell I have the Permatex counter book here?)

Die-Electric simply means it doesn't conduct electricity, so it doesn't contribute to voltage losses or shorted circuits to ground. It makes a great water proofer if you can keep it contained.
This stuff will burn though, so don't use it where it's going to be in the way of open sparks.
If you use it in your plug wire boots, you will need to find some way to secure the boots (a good idea anytime), or they will be lubed enough to climb the terminals and come off, so be sparing when you use it.

Just for your information...
If you ever have to replace the module in a GM HEI, you will need an extra kind of 'grease'. The module sheds heat by transferring it to the aluminum housing, and there is a special paste to help with this. (most commonly referred to as grease)
If your new module didn't come with a tube of the paste, you can get it at radio shack, or any TV repair place. It's the same stuff that is used under large power transistors for the same reason, to transfer heat.
This CAN NOT be interchanged with dielectric grease. The module paste is conductive to both electricity and heat, and in some circumstances is used to ground the transistors or what ever.
It's cheap insurance to make sure your new module lives on a hot day...

Later folks, Aaron.

So many cats, so few recipes...
 
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