I like the idea of these. Has there been testing done with these?
88' XJ LT1 Conversion and more
- Thread starter ibeanob
- Start date
I like the idea of these. Has there been testing done with these?
Well I spent the better of two days reading and researching and by most tests the Johnny joint seems to hold up the best. I am building this vehicle for the desert so I am not going to be doing any rock crawling like I used to in the Rubicon and therefore I'm not worried about binding. I am done rock crawling after 13 trips to the Rubicon and splitting my firewall open. I am building something to last in order to lower repair costs 
XJ LT1 Wiring :
I have had a hard time finding information on the wiring aspect of doing an LT1 conversion in a Cherokee so I thought I would try to give some input as I am going through it.
I started with the engine compartment and deciding what is needed. I found that most of the wiring on the passenger side was for the 4.0 and is no longer needed. I located several areas where groups of wires come out of the firewall as seen in the pictures. The fuse box is the obvious one but the others I am researching to find out where they lead. It appears that Jeep ran every piece of electrical wiring through the engine compartment, I am assuming for fire control.
So I started tearing apart the dash as I was going to need to in order to put in new gauges and switches. As I pulled things apart I labeled wire clusters with duck tape so I would not eliminate something I wanted or needed to keep.
I was thinking of making a custom gauge cluster similar to this one.
I have had a hard time finding information on the wiring aspect of doing an LT1 conversion in a Cherokee so I thought I would try to give some input as I am going through it.
I started with the engine compartment and deciding what is needed. I found that most of the wiring on the passenger side was for the 4.0 and is no longer needed. I located several areas where groups of wires come out of the firewall as seen in the pictures. The fuse box is the obvious one but the others I am researching to find out where they lead. It appears that Jeep ran every piece of electrical wiring through the engine compartment, I am assuming for fire control.
So I started tearing apart the dash as I was going to need to in order to put in new gauges and switches. As I pulled things apart I labeled wire clusters with duck tape so I would not eliminate something I wanted or needed to keep.
I was thinking of making a custom gauge cluster similar to this one.
- Location
- Rainy side of Washington
On a RENIX I know of several passthroughs on the firewall:
* There is one to the right of the engine, almost behind it. This is for the AW4 TCU.
* There is one on the left of the engine, almost behind it. This is for the ECU.
* There is the main bulkhead connector between the brake booster and the inner fender wall. That handles the fusebox and most other stuff.
On 91+ they eliminated the passthrough for the ECU and stuck it in the engine compartment. On 97+ they eliminated the AW4 passthrough as well, but added another to the far right side of the firewall IIRC for body wiring.
* There is one to the right of the engine, almost behind it. This is for the AW4 TCU.
* There is one on the left of the engine, almost behind it. This is for the ECU.
* There is the main bulkhead connector between the brake booster and the inner fender wall. That handles the fusebox and most other stuff.
On 91+ they eliminated the passthrough for the ECU and stuck it in the engine compartment. On 97+ they eliminated the AW4 passthrough as well, but added another to the far right side of the firewall IIRC for body wiring.
- Location
- Rainy side of Washington
I would say so, but there may be things I am forgetting.
Horns are also needed. And the fuel pump wire is somewhere in that bundle, since it's controlled by a relay under the hood. One of the fairly fat wires is power to the ignition switch, another few coming back through are power from the ignition switch acc/run/start output terminals, etc. I don't know RENIX wiring as well as I should, most of my knowledge is OBD1/2 based.
Horns are also needed. And the fuel pump wire is somewhere in that bundle, since it's controlled by a relay under the hood. One of the fairly fat wires is power to the ignition switch, another few coming back through are power from the ignition switch acc/run/start output terminals, etc. I don't know RENIX wiring as well as I should, most of my knowledge is OBD1/2 based.
Ok got it, thank you. I was able to isolate the ecu for the engine and transmission and removed them. I just finished labeling the instrument cluster wires. For smog reasons I have to mount the OBD jack and have an idiot light so I will be figuring that one out next.
- Location
- Rainy side of Washington
The way I usually do a wiring harness project is - I get the FSM out. Then I take the original harness and mark every wire where it goes through the bulkhead connector as to its purpose in life. Trim all the wires off as far into the harness as I can (to give as much length as possible for splicing) then take the engine donor and ECU+harness. Completely unwrap that harness of all tape and loom tubing, strip out any sensors/equipment I won't be using (figure out how to bypass or disable it if needed), remove all unnecessary wiring. At that point, there should be a pile of wires and connectors that need to be powered or supply power, etc, hanging out of the harness. Get the FSM for that vehicle out (it's probably already out, given what you just did stripping the harness down.) Figure out what each wire does, match them up with the ones coming from the bulkhead connector of the stock harness. In some cases you'll need to use relays or get creative, but probably not with a RENIX getting an LT1. Once that's all done, get the engine in and the harness halves in, locate everything how I want it, lash the harness up exactly how I want it shaped with a billion cheap zipties. Temporarily splice the ends of the wires together that I mapped out for each section of the harness, test fire it. If it fires up properly, shorten and splice each wire properly to match the intended harness path. If it doesn't, debug, then do the same. Then go over the whole thing with dry vinyl harness wrapping tape, removing the zipties as I go, then add loom tubing and electrical tape where needed.
Bam, now you have a factory-appearance custom harness that fits the vehicle perfectly.
Bam, now you have a factory-appearance custom harness that fits the vehicle perfectly.
Well I tore out the heater box today and did a complete rebuild on it including a new fan motor, heater core and weather stripping. I was able to purchase the weather stripping from the local auto parts store along with the other parts. It wasn't as hard as I thought but I came across a problem with the heater box mounting bolts. When I was pulling the unit out, one of the bolts next to the fan motor broke off. The actual plastic house the bolt was attached to on the heater box broke away causing a hole in the heater box. So I used Gorilla two part epoxy and repaired it but I knew the bold would no longer hold the box in place. I fabricated a pinch mount using some of the 10 gauge steel from reinforcing the frame and the fan mounting bolt.
The bolt without a nut is the one that tore away from the heater box.
These are the measurements I used to make the mount.
And this is the finished product. It seemed to work pretty well and re-sealed the fan to the firewall.
The bolt without a nut is the one that tore away from the heater box.
These are the measurements I used to make the mount.
And this is the finished product. It seemed to work pretty well and re-sealed the fan to the firewall.
To continue my wiring fun, I wanted to show pictures of what was removed. As you can see the only thing left on the passenger side is the cruise control, AC and heater wiring. On the driver side the only thing left is what is attached to the fuse box. I will be going through these wires this week and labeling them in order to determine what I am going to need.
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I just found a website that lists the pins in the fuse box at the firewall. This was very helpful rather than trying to weed through the system. http://s603.photobucket.com/user/trippleb_photo/media/YJPinouttoXJ.png.html
Here is the picture from the website
Here is the picture from the website
Started working on the gauge bezel today. I decided to make it out of .025 aluminum sheet. I used the original one for measurements down to the millimeter and then used tin snips and sheet metal pliars to bend the angles. I will probably weld in some supports on the back side but it feels pretty firm just how it is.
Here it is with the screws in
Here it is with the screws in
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Found some rust today while pulling up the carpet. One of the drain plugs had come out causing rust in the rear passenger side floor board. So I bought some pematex rust dissolving gel and rust neutralizing paint.
After following the instructions with the gel and washing it off, I started applying the paint which turns the rust black. You can see it starting to turn on the right side.
This is how it looked the next day after it dried. I am probably still going to weld in a repair patch to reinforce the area since it became pretty thin but I wanted to make sure the rust was neutralized first.
After following the instructions with the gel and washing it off, I started applying the paint which turns the rust black. You can see it starting to turn on the right side.
This is how it looked the next day after it dried. I am probably still going to weld in a repair patch to reinforce the area since it became pretty thin but I wanted to make sure the rust was neutralized first.
Finishing up gutting it out for paint. I decided to use Al's Liner to paint the entire jeep. I just need to find the pigment powder to match the jeep Baja Yellow.
Re: 88' XJ LT1 Conversion and mor
Well I haven't posted in a while because I have been swamped with other things. To make a long story short, I could not use the Al's liner because it was not tintable as it said. This was probably a mistake by the website I bought it from. I wound up going to a local shop http://www.macsdist.com/ and they suggested I use this stuff.
It worked much better and I am almost done with the under body (pictures to follow). This stuff is easy to shoot and the guys at the shop were able to get me the original Chrysler yellow that was used in the 80's. I will follow up with photographs of the gun they sold me and my progress. I determined I am going to have to shoot the vehicle with yellow primer prior to doing the exterior in bed liner due to the bed liner product being more transparent than regular paint.
Well I haven't posted in a while because I have been swamped with other things. To make a long story short, I could not use the Al's liner because it was not tintable as it said. This was probably a mistake by the website I bought it from. I wound up going to a local shop http://www.macsdist.com/ and they suggested I use this stuff.
It worked much better and I am almost done with the under body (pictures to follow). This stuff is easy to shoot and the guys at the shop were able to get me the original Chrysler yellow that was used in the 80's. I will follow up with photographs of the gun they sold me and my progress. I determined I am going to have to shoot the vehicle with yellow primer prior to doing the exterior in bed liner due to the bed liner product being more transparent than regular paint.
