Make a Comanche more garage friendly?

[NC Tom]

I have a hard time finding a good mechanic to work on my 88 with reliable results. I enjoy doing what I can myself. Time is the issue. I've been through three garage monkeys. Seems like they just don't know how to work on the Renix error, I mean ERA, jeeps.

 

So, can an old-@$$ MJ get un-Renixed to help future repairs be done more reliably, or do I have a better chance of finding Sasquatch?

[Comanche SS]

You can HO swap it, or 97+ swap it.

But truthfully, the renix is pretty easy to diagnose, without any special tools, if you can work a voltmeter, and know what you are looking for. 

The HO & 97+ swaps are also good options, but a lot of work, and both have pitfalls of there own.

[89 MJ]

I was going to say the same thing as Comanche SS. You can do the OBDI 91-95 HO swap, but I don’t think you’re gaining much over a Renix truck because the diagnostic tools don’t really exist for those either. At least for Renix, the REM exists. A 97+ swap gets you OBDII, but you’re still dealing with 25 year old parts. And in either case, you are rewiring most of the truck. 

[Pete M]

REM.

 

renix has pretty much all the same basic components as later years of XJ, and a lot of the same issues now that they are all quite old.  you just need to test things with a multimeter (or an REM) rather than more typical modern methods. 

 

what specific issue are you tackling?

[ghetdjc320]

Agreed on the REM. Problem is many mechanics rely on their scanners and not their skill sets. Kinda like going to the auto parts store and then asking what vehicle you’re working on when you ask them for a relay socket. You need the guy that knows where their reference books are. An OBD2 swap in an MJ is not a straight forward swap if done correctly. Cruisers tips and an REM are the way to go. But as mentioned, the wiring from headlight to taillight is now getting old and all the connectors are getting corroded. I’d note that MJ’s weren’t really built to a high standard . I still love these trucks but it is what it is

[NC Tom]

@89 MJ@Pete M@ghetdjc320 Thanks guys. I have an REM that I'm installing today. However, I'm not finding an easy path from the engine bay to the cab interior.

[89 MJ]

I ran the cable for mine across the firewall and then inside the cab near the brake booster and fuse block area if I remember correctly. You don’t necessarily need it inside the cab with though. It might be nice to have it so you can walk around the engine compartment with it in your hand. 

[NC Tom]

1 hour ago, 89 MJ said:

I ran the cable for mine across the firewall and then inside the cab near the brake booster and fuse block area if I remember correctly. You don’t necessarily need it inside the cab with though. It might be nice to have it so you can walk around the engine compartment with it in your hand. 

 

Yeah, right after I posted I went back out used that same hole. I decided to mount it inside. Unfortunately, it doesn't fit tight. It's too far left and overlaps the screen a bit and I can't set the clock. Looks like a I'll need to modify the dash a bit.

 

BTW, how the hell do you get the dash cover off? I've cracked mine. It will break in half next time I try.

[fiatslug87]

If it’s that weakened, I would loosen the steering column support rods and drop the column a little.

[NC Tom]

4 minutes ago, fiatslug87 said:

If it’s that weakened, I would loosen the steering column support rods and drop the column a little.

Dang! Is that easier then it sounds?

[89 MJ]

Its pretty easy to drop the column down a little bit. I don't have a tilt column, so it isn't too bad, but its still scary. I just figure that when I break it, its an excuse to get the brushed silver one

[AnotherOldJeepGuy]

1 hour ago, NC Tom said:

BTW, how the hell do you get the dash cover off? I've cracked mine. It will break in half next time I try.

I usually park in the sun with windows up for a while to make sure the plastic is nice and warm.  Of course once the crack has started that might not help.  If the crack is clean you might glue it back together with E6000, that stuff is really strong and retains some flexibility.  I hunted down cure times since that is not on the packaging and found something about 72 hours for maximum, so I generally let it set for 3 days.

[GonzoTheGreat]

2 hours ago, fiatslug87 said:

If it’s that weakened, I would loosen the steering column support rods and drop the column a little.

X2. This has worked great for me. 
 

2 hours ago, NC Tom said:

Dang! Is that easier then it sounds?

yes. The whole column is attached to two studs, one on each side. Loosen both nuts so there are just a couple threads remaining, and the whole column drops a little. Then pull the dash bezel straight out. You still might have to squeeze it a little, but you shouldn’t have to force anything. 

[pizzaman09]

I'm surprised the REM isn't centered in the hole, mine is dead center.  Was your original clock in the center or did you just have a blank panel?  I almost wonder if you managed to get it installed to the left of the mounting screw.

[NC Tom]

On 5/4/2025 at 6:21 PM, AnotherOldJeepGuy said:

I usually park in the sun with windows up for a while to make sure the plastic is nice and warm.  Of course once the crack has started that might not help.  If the crack is clean you might glue it back together with E6000, that stuff is really strong and retains some flexibility.  I hunted down cure times since that is not on the packaging and found something about 72 hours for maximum, so I generally let it set for 3 days.

It's pretty clean. Warming the plastic is a good idea.

[NC Tom]

31 minutes ago, pizzaman09 said:

I'm surprised the REM isn't centered in the hole, mine is dead center.  Was your original clock in the center or did you just have a blank panel?  I almost wonder if you managed to get it installed to the left of the mounting screw.

It's odd. I had replaced the factory clock. Mounting holes all line up. I thought maybe I could loosen it and shift it over, but there is no play there. I may go back and enlarge holes, with a hole stretcher of course, to get a little shifting room.

[rokinn]

Wax paper on the column helps with removal also.

[89 MJ]

You can also use a smoke machine to help find vacuum leaks. 

[watchamakalit]

3 hours ago, 89 MJ said:

You can also use a smoke machine to help find vacuum leaks. 

I was always taught to just use the Marlboro I was smoking. Lol