Project: Slippery Slope – a ’91 MJ runner

[eaglescout526]

What job does each of those relays have inside?

[Gjeep]

These are only present HO years in this location -- 2 are factory (dash illumination & horn) and 2 are from me (starter kill & dome light supervision when doors unlocked). 4 relays fit there perfectly without hitting metal support structure of main dash. 

[eaglescout526]

Neat!! Didn’t know that. 

[NickyV]

Is the starter kill a security feature? I've been thinking about how to add an extra layer of protection to my MJ besides Ye Olde Club.

[Gjeep]

Not from the factory. Its a me add on via an old Viper brand alarm. Jeep did have a problematic security system in 91/92 for the higher end XJs but the MJ never got it. And majority of XJ owners I understand uninstalled it because it was leaving them stranded. I wanted all the lock/unlock features of a ‘modern’ truck since I took the time to add power windows and door locks. There are a couple ways can wire a kill switch solo though. 

[jodawill]

On 12/23/2024 at 5:18 AM, Gjeep said:

Key Parts parts installed – new set of repop taillights and linkage bumper set. As always, I try to avoid installing with rivets, so a stainless steel truss screw was used instead.

 

 

 

 

This MJ will also get a power actuated tailgate lock similar to my other MJ tied into the power door lock wiring. The wiring isn’t as pretty as in my other MJ as I am constantly reminding myself to keep the focus of this build as a runner – an MJ to be used.

 

 

Full window upgrade installed and working. 97+ XJ door handles were installed as I like the look of them over the original. New door to body bumpers and various plugs installed, in addition to fresh door lock cylinders to replace the brittle factory installs.

 

 

And finally, the floorboard was POR15'd for a long and rust free life.

 

 

Where did you get those tailgate bumpers? I see some on eBay for $40. I'm not sure what the quality is like.

 

Edit: I found a post about the Key Parts one on eBay. It sounds like that's the closest to the OEM parts, so I ordered them. I'm glad I saw your post! I didn't know you could buy those. Mine are in rough shape. Thanks!

[Gjeep]

I got to cutting on an XJ roof rack for the MJ 80’s inspired light bar. Lots still to do around drilling another mounting hole on each rail, strategy around the holes needed for wiring and overall clean-up/ paint. Here she sits – not attached to the roof at all hence the gap between the roof and roof rack rail. I’m feeling good about this light bar, just not looking forward to drilling the hole at an angled surface…

 

 

 

Also finally got around to bleeding the brakes after all the new parts were installed months back. Had a heck of a time with the front passenger line not bleeding/ getting any fluid. Zip. Nada. Never had something like that happen before so I took to Googling — the answer and fix — stomp on the brake pedal repeatedly. It resets the proportion valve to all open. Like I said, first time I experienced an issue like that. Brake booster (’95 XJ) and proportioning valve (’88 XJ) were NOS.

 

Plug for the Motive Bleeder. I’ve been using mine for at least 20 years and it’s great. They sell different auto manufacturer caps to work with their main canister.

 

[Gjeep]

Finally got to it – AC is charged; R134a conversion using factory ’95 XJ parts as in my other MJ. Hard to tell how cold it truly blows as it’s at best 50* here currently. If the temperature gun I used was correct, the MJ was blowing 38* yesterday but want to confirm. Will retest. Where’s the sun when you need it... Testing the HVAC wasn’t without its challenges, as I could get the bezel control to open/close any of the doors. Pulled the vacuum lines off the back of the bezel and nothing. Assumed a vacuum leak but couldn’t find any. After walking away for a bit I thought I’d take a double-take at the check valves – one off the intake manifold and the other near HVAC side firewall. What was there I didn’t recognize. I pulled them both and noticed how tiny the port was where vacuum passed. Replaced them both with parts bin factory check valves and all started working again. Curious though for any who own a ’91 MJ if yours has these same check valves from the factory. I don’t recognize them.

 

 

 

First pass at drilling holes on the lightbar I’m building out of an XJ roof rack, and everything worked out. I’ll be running wiring through the driver’s side channels near invisibly. You can see the small hole in the end cap it will run through then into the roof. They still need to be cleaned up and painted.

 

 

 

 

Also got to rewiring the IPF headlight harness as it doesn’t play well with the Holley RetroBright headlights I’m going to be running. The IPF harness is great for standard headlights but doesn’t run its power correctly for the MJ to use RetroBrights with it. Kudos to Red Mistress for giving me the heads up on these. All my Jeeps will be getting a set.

[Eagle_SX4]

4 hours ago, Gjeep said:

Curious though for any who own a ’91 MJ if yours has these same check valves from the factory. I don’t recognize them

Those look to be dorman check valves. Which seem to be the most available aftermarket ones.

[Gjeep]

I finished cutting and drilling on the XJ roof rack – it wasn’t nearly as challenging as I thought it would be. Got lucky. It came out well but still need to refinish these parts and nutsert the roof/ run wiring invisibly. This MJ will be running NOS Wrangler TJ rounds in front and up top.

 

 

 

I decided also that I want some thump in the MJ. I ran this same Pioneer unit in my other Comanche, but two of them tucked behind the seat track versus under. Unfortunately, the driver side doesn’t have enough room under the seat track thanks to the girthy tunnel. And since this is meant to mostly be a work truck I’m only running one sub this round. It will be disassembled and painted black to match the rest of the interior even though it's tucked away.

 

[Gjeep]

Just as I straightened up the driver side wiring, I made a mess passenger side. The under the seat Pioneer sub is installed (140W). It’s nothing crazy but adds decent thump when needed.

 

 

RediRad is the aux unit I installed in my other Comanche that got me to BlueTooth. Last time I spoke to the owner (husband and wife team, product made in USA) close to 4 years ago they were closing their doors… so I purchased a round of the latest aftermarket BT add-in’s over the past couple weeks, tested them out and they all sounded like crap with the stock head unit. Took a gamble at reaching out to the RediRad mom & pop shop and found out that they reopened due to the demand half time while looking to expand. I wasted no time buying one of their units. Basically, it’s a go-between on the co-ax cable/ FM modulator with ignition-sourced power and ground. That’s it – and you get a 3ft long aux cable to plug in to your phone/ device. From that point I added a USB BT, ground loop noise isolator, splitter and then a hard wire USB/aux run going inside the center console that powers the phone and serves as a hard wire option for music. I have the option of BT or not.

 

[ghetdjc320]

Out of curiosity, have you seen the Focal under seat passive subs? I was seriously looking into these as an option when I was sorting audio. Not sure how they would work with the stock brackets though. I measured them for my corbeau brackets and they looked like a perfect fit. 

[Gjeep]

Sure did -- too big. I was at first open to some trimming of the factory seat bracket but the amount that needed to be removed would make the seat no longer safe. Possibly trimming the repop MJ brackets that are a much thicker gauge metal could work, but in the end for my needs these Pioneers sound good especially when running 2 of them tucked under the backside of the seat/floor as in my other MJ. I don't know about the Corbeau brackets and what kind of space is under there. There is an odd but do-able option of running the first gen seats on 2nd gen brackets. I recently saw an adapter online to make that happen. You'd also need to add in the mounting crossmember both driver and passenger side floorboards -- but there would be enough room as I'm running similar sized subs in my kids newer XJ's and they have plenty of room. Again, an odd option. But an option.