I've always heard you Jeep guys complaining about how your CJ's electrical system had issues and often running all new wires was the only way to fix the problems. It never made much sense to me, because everything worked when the Jeep left the factory, why shouldn't it work now? Well, I always just figured someone messed with the factory wiring and that's why it was haywire.
Hi everyone, it's me, Randy again. I have no idea why the Jp magazine editors keep asking me back to do this column. Earl gets bored after I tell him like half the information of even one page. Heck, even Crab-Man doesn't like listening to me go on and on about electrons and whatnot. But, for some reason those editors keep inviting me back, and so this month I want to talk about some bulky connectors. This one is out of a CJ, but most of the AMC Jeeps had something similar and I'd bet Mr. Turtle that yours needs cleaning by now.
Anyway, I've seen the bulkhead connector become a problem in a bunch of AMC-era Jeeps, and this one was no different. As you know, the fuse block is inside the Jeep on the firewall in front of the driver. Well half of the circuits that the fuses in that block protect are outside the Jeep, and the power needs to get through the firewall. So, AMC came up with this bolt-together electrical connector. It is often called a bulkhead fitting, and that's what I want to talk about today.
I have seen with my own eyes all kinds of things go wrong with the connector, but aside from the bolt loosening up (go and check to see if yours is tight), the most common problem I have seen is that they get dirty and need a good cleaning. When the Jeep left the factory, AMC put grease in there to keep the contacts from corroding, but years of road dirt, off-road dirt, and even possibly mud could have worked its way in there. AMC ceased making Jeeps 22 years ago, and that means that the grease that is in there is at least 22 years old. Would you run 22-year-old grease anywhere else in your Jeep? Open that thing up and clean it.
When you remove the bolt from the connector, and start to "unplug" the connector, do it slowly, and make sure the fuse block doesn't jiggle around too much. Having a friend to hold it can help. The seal between the fuse block and the firewall is likely brittle after all these years. After you disconnect it, follow my guideline below for cleaning, and be sure to search for any broken, bent or deformed terminals before adding new dielectric grease and putting it back together.
Even the outside part was...
Even the outside part was dirty and nasty, thanks to the 30 year old grease. Again, I hit it with some brake parts cleaner (Electric parts cleaner just couldn't touch this), and then broke out the old toothbrush. Don't use your wife's toothbrush, you'll never get it clean again- even bleach doesn't work. This nice picture of nastiness is after only a few seconds of scrubbing.
Even with a stock, unmolested...
Even with a stock, unmolested bulkhead connector, crud can still get in there. And, when you consider that the Jeep this came from is almost 30 years old, it makes sense to clean it. When I took it apart, I found nasty grease, and mud caked into a few of the terminals. So, I hit it with brake parts cleaner and let it sit. This is the inside part, aka the back of the fuse block.
Now, I took this one apart...
Now, I took this one apart just to see what the inside looked like. There was mud caked to the outside, so I figured some cleaning could be needed. Once I had it cleaned out a bit, I found one of the terminals had heated up enough to melt the connector, and thus not make contact anymore. I was able to get it back in place, and with some glue it stayed where it belonged, and with new dielectric grease, there will be no more electrical issues from the bulkhead connector.