Electrical 1985 CJ7 needs a lot of help

[AndyCJ7]

I have a 1985 CJ7 that's had some modifications done to it by previous owners. The engine and mechanicals are mostly stock but all the emissions components have been removed.

The wiring is a complete mess. There are free wires hanging in the engine bay, zip ties holding some things in place, wires outside of looms everywhere, etc. Most of the lights work, except for one of the front turn signals (it's not the bulb). The voltmeter gauge works. There are aftermarket mechanical gauges that don't work, and the factory oil pressure gauge has been replaced with a printed piece of paper. There's an aftermarket tach that works and the speedometer moves but I haven't driven it enough to know how accurate it is.

The vacuum system in the Chilton's manual looks pretty complex, but mine looks a lot different. I have a single vacuum line to the distributor and nothing else. There are no EGR solenoids, charcoal canisters, or anything else. The fuel vapor return system is gone as well.

It has a duraspark-II ignition - I'm pretty sure, at least. The white wire that connects to the ignition module seems to be one of the wires that ends in the engine bay. It's not connected to anything. I'm not sure what it's supposed to be connected to but it seems to run fine without it.

I've driven it around on some short trips. Fuel drains back into the tank pretty quick so if it sits for a few days it takes a bit to start. I drove it once about 20-30 minutes and it just lost power and died and wouldn't restart. It kind of seemed like vapor lock to me. Once it cools off it's fine. How likely is it that the missing fuel vapor system is why it doesn't like to run for too long?

I would like to upgrade to power brakes. Does anyone have any information on converting to the teardrop style intake to make room for the booster and master cylinder (without spending a ton of money)? I also notice that the front brake line from the master has been replaced (with a hand-bent, coil-less piece) and the rear one looks pretty weak in places. I probably will replace the whole brake system. Any tips/advice on that?

 

[Armyvet25]

Dude...Jeez...talk about a shopping list, ok, for starters, get you an oem style manual say off of Flea-Bay, will be well wort your trouble, next, read it cover to cover till you puke-seriously. Next DETAILS, engine, trans, T-case, and take a bunch of pics, underhood etc. Then maybe tackle one thing at a time, like maybe finding a new or used good condition replacement wiring harness. Get the pics and details, buy a manual, others will chime in and be glad to help, baby steps lol.
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example--->manual
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ok, I see from the signature, it's a 258

 

[Belizean]

X2 on THAT manual. Not perfect but a lot of info you need.

 

[CJ]

Dude...Jeez...talk about a shopping list, ok, for starters, get you an oem style manual say off of Flea-Bay, will be well wort your trouble, next, read it cover to cover till you puke-seriously. Next DETAILS, engine, trans, T-case, and take a bunch of pics, underhood etc. Then maybe tackle one thing at a time, like maybe finding a new or used good condition replacement wiring harness. Get the pics and details, buy a manual, others will chime in and be glad to help, baby steps lol.
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example--->manual
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ok, I see from the signature, it's a 258

Or get the FSM here @ Jeep-CJ.com -->> CJ Factory Service Manual 1984 - 1986

 

[Armyvet25]

Awesome Scott, didn't realize it was here

 

[AndyCJ7]

OMG that's great information. I can't promise that I will read it cover to cover, but I will familiarize myself with it. It's a great place to start, thank you!

I think I want to get the fuel system straightened out first. I think the fuel vapor system is why it doesn't run right. The other stuff on the list will have to wait a bit. I'm not really interested in restoring it to 100% factory specs, especially the emissions stuff. I just want it to run decent so I can take it to the beach and not worry about having to tow it back.

 

[AndyCJ7]

It's a 258 straight six with a T5 manual and a Dana 300 transfer case.

 

[Armyvet25]

You mentioned vapor lock even if not by name, get your self a fuel filter with 1 inlet 2 outlets, single inlet from the tank, the smaller outlet returns to the tank and the other to the carb, and make sure your lines aren't running along the block or exhaust. Should cure the fuel no start issue, but next time it does it, disconnect at carb, pull coil wire off of dist, crank and see if you have fuel pressure, maybe carb going out after heating up, diaphragm failure.

 

[j6824]

Determining what carb is on it would be a god place to start

 

[Armyvet25]

and read it cover to cover or your going to the tool shed....

 

[TSB8C]

Great resource for the fuel line routing, with diagrams, including the filter (as mentioned above by Armyvet25) and other resources:
link to thread

 

[AndyCJ7]

Determining what carb is on it would be a god place to start

It sure would. I don't think it's a stock carb. It says 'Holley' and it's a 2bbl but there aren't any other markings that I can see. I've googled how to ID a holley carb and read lots of articles but my carb doesn't have any markings. I'll get some pics of it.

The return spring is hooked on to a hose clamp. I'd be interested to see what the stock setup looks like.

I'm not super familiar with carbs.

 

[AndyCJ7]

Carb pics.






Here's my awesome throttle return spring setup:

 

[AndyCJ7]

I also found a dead wire coming from the ignition module. How does this thing run?

The white wire goes through a 2-wire harness and it comes out blue on the other side. The blue wire goes nowhere. It just ends in the engine bay, not connected to anything. What does it do?

 

[TSB8C]

Perhaps one of these can help on the ignition wiring question. I believe that white wire going through the 2-pin connector and coming our blue on other side is the white wire from your ignition module to the "crank" or "S" (start) blue wire on the solenoid (which also has a blue coming from the "start" position on the ignition switch) - see the second image bloew where I circled what I believe are your wires in question.

 

[AndyCJ7]

I found a dark blue wire from the S terminal of the starter relay that went through the harness and over the valve cover. It came out of the harness near the firewall pass-through and just ended. I noticed that the wire from the DS-II module seemed to be a different shade of blue.

Should I connect these two wires? It seems like I should but I wonder what it's going to do. I'll give it a try this weekend.

 

[TSB8C]

I believe that blue wire from the "S" terminal on the solenoid going to the bulkhead connector on the firewall should be the one that goes in and under the dash to the starter switch. That would be the wire that connects to the "START" position on the starter switch to engage the solenoid. The blue wire from that 2-pin connector with the white coming in the other side of it and going to the ignition module is how the ignition module gets its signal that the engine is cranking. But if as you say that blue wire is "just ended" at the bulkhead connector on the firewall and does not pass through to the ignition switch, then a PO has connected some other wire to engage the solenoid when the key is turned to "START". That would also seem to indicate that your ignition module is not getting the signal to know when the engine is cranking. That would make for hard/failed starting.

You may be best to get a new wiring harness from Painless or another. I actually pulled my three harnesses (engine bay, under dash, and rear) and re-worked them myself on the dining room table with an electrical meter, a soldering iron, and heat shrink tubing. But I have an electrical background and lots of CJ wiring experience (owned 3 CJs for a total of about 30 years), plus I was making custom changes/additions (LED conversions, keyless/remote start, switched from manual to auto trans with different BU light and neutral safety switches, dual batteries, digital gauge setup, fuel injection, etc). But for someone not that familiar with the wiring, reading schematic diagrams, and using an electrical meter to trace stuff out, you'll probably end up chasing electrical gremlins for a long time trying to deal with all the unknowns from one or more prior owners of your rig.

Brand new harnesses from Painless or Omix or Centech Wiring are indeed pricey, but nice. But some used OEM ones are available on eBay for $100 - $150. One example: eBay link to CJ harness

 

[AndyCJ7]

One of the many mods done to this jeep was a conversion to push-button ignition. There is a second wire coming from the S terminal on the relay that goes to the start button on the dash. I have a feeling this was done because the ignition cylinder in the column broke. I actually don't mind the push button start at all.

I might have mentioned it before, but as long as the fuel hasn't drained back to the fuel tank, it fires right up.

I looked under the dash and it's a rat's nest of wires, wire nuts and electrical tape. I have seriously thought about putting in a painless wiring harness. I think that would solve a lot of problems.

 

[Project86]

Sounds like you are at a crossroads. Either continue to work with ya' got or strip it out and go with something "new". Sometimes a piece of mind is valuable when you are a long from home. IMO, I'd take the time and start with something new/better/updated (whatever word works for you) and know what I was up against if an issue popped up. The other thing you may be up against is time itself. If ya' got a hard on to go wheelin' then fix what ya' got. If ya' can keep your pants on until it's truly right then replace with the upgrade, which ever you choose.

 

[Patrick]

Good advice .

Gasoline is not draining back, it’s evaporating.

I would invest in new turn signal and ignition switches, fuel pump, and carb kit. Replumb your fuel circuit with the right filter and line selection. Don’t diagnose, just replace these items.

As for your wiring (assuming the fuse block is good), cut and remove any and all wires, mods, or components that are not original and bring back to factory stock as much as possible. Reextend wires to original form. Good quality terminal kit and tools will help.

You’ll need a lot of patience, don’t get overwhelmed. Good luck.