AZJeff

Wire nuts have NO place on automotive applications. For starters, they don't hold well in high vibration environments such as vehicles. Secondly, they are not sealed from the elements at all. Moisture will get into such joints and cause corrosion of the individual strands of the conducting wires and eventually create an open connection. The BEST connection of two wires is solder, with an outer coating of heat shrink tubing. Barring that, a crimp type connector with an outer covering of shrink tubing that contains adhesive is the next best choice.

Here is my list of tips from that thread, repeated for posterity: I have owned multiple XJ's and now an MJ here in Phoenix, and all of them have run just fine in the heat. The secret to that is to make sure your cooling system is operating AS DESIGNED by Jeep. If ANYTHING has deteriorated below OEM spec, overheating is likely. Here are my thoughts: 1. I don't trust the temperature gauge on the dash to be particularly accurate. I alway confirm temperatures by using one of the infrared meters with a laser pointer on it (Harbor Freight for the win.), and I take my temps on the thermostat elbow. By doing that, you can sort of extrapolate how far off the gauge on the dash is from reality. 2. If your coolant is even the slightest bit cruddy, a flush is the minimum to do. When you refill, be sure you run the correct mix of antifreeze, because it not only lowers the freezing point, but it raises the boiling point of the coolant as well. 3. If your viscous fan clutch is more than 5 years old, replace it, regardless of if it "feels" OK. 4. If you don't have the electric fan in your MJ, install one (An improved one was used in the 97+ XJ, and is a worthy upgrade.). 5. If your radiator has any crud that does not come out from a good flush (an inspection mirror and flashlight is needed to see inside the end tanks to look for permanent deposits in the radiator), then consider converting to an open cooling system while you are replacing the radiator. It removes a bunch of weakness with the closed system pressure tank and cap. 6. If you are redoing the system to convert to open, ditch the heater control valve while you are at it. That plastic piece of junk is prone to breaking, especially with the heat we see out here. 7. If your hoses are even the slightest bit soft, you can expect them to get MUCH softer very soon with the higher under-hood temperatures. I just automatically replace mine as soon as I see or feel any squishiness at all. 8. While you are changing the hoses and/or the radiator, put on a new belt if the one you have isn't new within the past 5 years was well. The heat kills those things as well. I know guys who run the hood louvers, but I am not convinced it really helps the actual engine cooling that much. It might make the temperature of various components lower, but actual engine temps are not going to be improved that much.

If your original headliner backer board is solid, removing the old headliner fabric and installing new stuff from the vendor of your choice is pretty straightforward. There are lots of YouTube videos on how to do it for a Cherokee, and an MJ is just a smaller version of that. There are also “how to” sites on how to recover the sun visors as well. The job doesn’t require lots of special tools, just clean hands and patience.

Order the ones for the 96 XJ, and they will fit fine on your MJ.

Given the age of the OP's vehicle, getting an OEM clutch and an OEM electric fan is about zero. That means aftermarket stuff. Buying from the local auto parts store is a crap shoot, and most of the time, the stuff comes from China, which always makes me leery. At least going to Rock Auto, you get to see what brands of stuff they offer, and choose accordingly. My MJ has a e-fan made by Continental, which although it is not OEM, it is a reputable brand out of Europe. The fact I could choose that brand (along with ones from China) on Rock-Auto makes them one of my favorite places to shop.

Yeah, but the older fan, if working as intended, should not cause total overheating like the OP is reporting. The new fan should just give a bit more margin. I am sort of stumped here. The "plumping" of the coolant tank is to be expected, especially when it's older. I was expecting the OP to report some sort of pressure loss at the cap, since that is a COMMON issue with older closed system tanks. I keep going back to the fact that the vehicle only overheats when stationary. That is almost ALWAYS a sign of lack of airflow over the radiator. (I had an F150 that would do the same thing.) OP---I have a question. When your AC is running, and you come to a stop, does the interior cabin temperature start to climb noticeably? And then once you start moving again, it cools back down to what it was before you stopped?

So if you can escape traffic, and begin cruising at a steady 40+mph, do the temperatures return to the normal range? If it does that, it sure implies that not enough air is moving across the radiator when the vehicle is sitting still to dump the heat being put into the rad. Once vehicle speed raises the air flow rate, then the radiator can do it's job correctly. I am going to ask another question--do you have a OEM fan shroud around the mechanical fan?

It sounds like you are getting properly correlated temperature readings on the dash. I am wondering why they are so high, even for this area. From what you are saying, your high temperature problem is most evident in traffic, when airflow over the radiator is lessened, and the radiator cannot dump the heat generated by the engine. That can only happen if coolant flow in the radiator is reduced by some reason, or if air flow over the radiator is not adequate. 1. You have a new radiator. I assume it is at least the OEM 2 row type, correct? 2. Is your radiator filled with a 50/50 mix of antifreeze and clean water? 3. Have you confirmed the electric fan is working, and coming on when engine temperatures reach about 215*? 4. What is the condition of the thermostat in the engine? You say it is new, but have you actually checked its' function outside the vehicle? 5. You say you have a new clutch fan. Does it seem to be functioning as expected? (I wonder if it's defective.) 6. Does your MJ have factory AC? If so, is the condenser free of any obstructions of airflow? (dried mud, tons of dead bugs, etc.) I am looking at ways the radiator isn't getting the airflow it needs. 7. Are your upper and lower radiator hoses nice and firm (when cold)? A soft lower hose can collapse under water pump suction, and restrict coolant flow. One last question: when the engine temperature begins to take off for the moon, does the engine actually begin to boil over via the pressure tank, or has the tank and it's cap contained the pressure while it's exceeding normal limits?

Temps climbing rapidly in traffic is normally a sign of lack of airflow over the rad due to fan issues. when you put in the new rad, what did the old coolant look like? The guy @GrandBoost talked about had massive crud in his cooling system, and that will plug up a radiator pretty quick. have you correlated instrument gauge readings with measured temperatures out at the thermostat elbow, BTW?

If you are still seeing operating temperatures of over about 215* when ambient air is at 110* (or thereabouts), then something in your cooling system is not up to OEM specifications and performance. The two things people often "think" are OK, but are not, are the radiator proper and the viscous clutch fan. The radiator might flow water just fine, but if the passages have lots of corrosion or mineral buildup, they cannot transfer the heat as required. The viscous clutch fan is notoriously hard to actually confirm as working correctly. My rule is that anytime that is over 5 years of age, it gets replaced. Finally, as Pete said, if you don't have an e-fan, get one installed. My efan comes on regularly even when my AC is not running in the hot weather, and that tells me the viscous fan alone cannot cool a 4.0 when the ambient air is 110*

There was another thread on this topic about 10 days ago where I spelled out the magic formula for how to keep an XJ or MJ operating at proper temperatures in Phoenix heat. And that heat is about as high as you will see regularly inside the US. check out that thread, and follow the suggestions as needed to have a happy Jeep in the heat

Its quite possible that the original design called for a screw to be located there, and they removed it as a cost cutting measure when they found it did little to help the panel security. I put one in that position anyhow on my MJ, as I figure the more secure stuff is, the less likely it is to squeak and rattle.

Agreed. Mild soap (dish soap) and a hose with a nozzle will do a pretty good job. Just be sure to rinse the fabric well so no soap is left behind. As Eagle Scout said, make sure the belt is left fully extended until dry. Hand it up in the sun, or with a fan blowing on it, will help speed the drying.

Yeah, we old guys gotta stay together. You know how there is "boomer bias" nowadays

Send me a private message, and we can set u a visit to my home garage in Queen Creek. (See my note on the original thread on this topic.)

Boy are you ever old. (Said by someone who has two years on you!)

If your MJ is fully drivable, I would be willing to help you out with looking it over and discussing a strategy on what to do to bring the cooling system up to snuff. Best of all, if something REALLY needs attention RIGHT AWAY, I have something that is VERY valuable here in Phoenix: and air conditioned garage. Send me a PM and we can set up a "look it over" visit, if you like. I am in Queen Creek, which is about 25 miles from Tempe.

I don't know of any that I have used, because I do my own repairs. Other guys on the forum who are in AZ might be able to chime in on some reputable shops in Maricopa County. What part of the Phoenix are do you live in?

I have owned multiple XJ's and now an MJ here in Phoenix, and all of them have run just fine in the heat. The secret to that is to make sure your cooling system is operating AS DESIGNED by Jeep. If ANYTHING has deteriorated below OEM spec, overheating is likely. Here are my thoughts: 1. I don't trust the temperature gauge on the dash to be particularly accurate. I alway confirm temperatures by using one of the infrared meters with a laser pointer on it (Harbor Freight for the win.), and I take my temps on the thermostat elbow. By doing that, you can sort of extrapolate how far off the gauge on the dash is from reality. 2. If your coolant is even the slightest bit cruddy, a flush is the minimum to do. When you refill, be sure you run the correct mix of antifreeze, because it not only lowers the freezing point, but it raises the boiling point of the coolant as well. 3. If your viscous fan clutch is more than 5 years old, replace it, regardless of if it "feels" OK. 4. If you don't have the electric fan in your MJ, install one. 5. If your radiator has any crud that does not come out from a good flush (an inspection mirror and flashlight is needed to see inside the end tanks to look for permanent deposits in the radiator), then consider converting to an open cooling system while you are replacing the radiator. It removes a bunch of weakness with the closed system pressure tank and cap. 6. If you are redoing the system to convert to open, ditch the heater control valve while you are at it. That plastic piece of junk is prone to breaking, especially with the heat we see out here. 7. If your hoses are even the slightest bit soft, you can expect them to get MUCH softer very soon with the higher under-hood temperatures. I just automatically replace mine as soon as I see or feel any squishiness at all. 8. While you are changing the hoses and/or the radiator, put on a new belt if the one you have isn't new within the past 5 years was well. The heat kills those things as well. I know guys who run the hood louvers, but I am not convinced it really helps the actual engine cooling that much. It might make the temperature of various components lower, but actual engine temps are not going to be improved that much. Also, get some oven mitts or gloves to carry in the Jeep. When I have been out running around and its fully heated up in the summer, I can barely even reach in to release the secondary hood latch due to the heat of the hood by the radiator. Then, once it's unlatch, I race to move sideways over towards the prop rod area, where it is MUCH cooler. Gloves make this a bit more tolerable, and you won't look goofy like I do when crab walking the hood in my hands to get to the cool part

Gotcha. Thanks for the explanation.

As we all know, the MJ tailgates have two red lenses, each in their own compartments in the light assembly. There is also a back-up light in its own bottom compartment with a clear lens. So my questions are: 1. which of the two red light compartments does the turn signal junction? 2. Which of the two red light compartments do the brake light function? 3. And finally, do one or both of the compartments act as tail lights? Thanks

I will affirm the comments from Cruiser related to techs. at the Jeep dealer(s). I had a cruise control issue on my 2000XJ a few years ago that I could not fix, since I did not have the Chrysler-specific "DRB" scanner that can talk to the cruise control functions in the PCM. I took it to the nearest dealer, and the dealer said they had no techs that could diagnose the issue. I called the next closest dealer, and explained to the service advisor I used with warranty issues on my 2014 Wrangler about my problem on the old XJ. He said they had ONE TECH. in the shop that had worked long enough to be familiar with the 2000XJ cruise control. (He had been working on Jeeps since the end of the AMC era He was able to fix it, and he used it as a learning experience for one of the younger techs. on how old Jeeps were constructed and functioned, and they enjoyed looking at my fairly nice old XJ. Taking one of our MJ's (or an XJ for that matter) to a Jeep dealer for repairs would be like asking a Ford dealer to work on a 1969 Mustang Mach One. They would be clueless, for the most part.

Core4x4 for the win, even with 33” tires

Take one of your existing carrier bolts to the local hardware store and match thread diameter and pitch against the stuff they have in stock. That now gives you the proper tap size to use. NOTE: I am NOT suggesting that hardware store bolts can be used in place of the OEM bolts. The OEM bolts are SAE Grade 8, and probably a lot higher grade (stronger) than anything your local hardware store might stock.

The wires to the seat belt switch, in the 1991 manual I have are shown to be a black one and a white one. These, of course, are not the colors of your two wires Others have mentioned that they suspect a ground issue, and I think they are on the right track with the root cause of your problem. The circuit is very basic for that seat belt switch. One end goes to power on the chime module, and the switch just completes the ground to the other side. I outlined this is blue on the attached diagram. The location where it completes the ground is a common ground for a ton of stuff, so my inkling would be to ground one of the wires and see what happens. I know that kinda sounds kind of a guessing approach, but since the wire colors don't line up, it's worth a shot.