ghetdjc320

I thought I’d start a thread on the frequently recurring topic of engine cooling. I’d love to see some club input on the various problems/solutions to this issue. Something we can reference going forward. Obviously, there are many factors that contribute to overheating but I wanted to touch on a few common ones along with some of the common fixes. All too often we see some new cooling system “upgrade” that touts some miraculous cure for overheating. But did it actually improve something or just fix something that was broken or that was already end of life? The ones that we see a lot of are (in no particular order): 1. High flow water pumps 2. Multi-Core radiator upgrades 3. Triple e-fans or a variation thereof 4. Water wetters and coolant additives 5. High flow thermostat housings 6. Hood vents 7. Heat shielding products 8. Low temp thermostats Anything else I’m missing on this list?? The underlying overheating issue we see (in no particular order) 1. Clogged or dirty radiator/coolant passages 2. Bad water pump 3. Coolant system leaks 4. Cracked block/head/blown head gasket 5. Lean running condition 6. Incorrect coolant fill 7. Bad thermostat 8. Failed Renix temp/fan switch Anything else I’m missing on this list?

I actually need some of these as well. Lmk if you find one that works.

Looking great! Were you planning to do any upgrades to the AX15?

I haven’t dived into the cassette mechanism at all but with as many small mechanical pieces as it has, I don’t really want to work on it. That being said, I already have a couple of good tape decks I could easily swap in for the RX-173 if yours is bad. You mentioned yours isn’t working, which model is it?

A light filter should accomplish that. The factory uses a blue filter. Coupled with the yellowish tint of the incandescent bulb, it gives off a pale green glow.

That particular section of the steering column where those bolts lie, is very deep in the column. I can’t see anything that would be accessed in the part of the column that is not already accessible. One of the few bolts I wouldn’t mind welding in place . It should be noted though that even without the full disassembly, you can access one or two of those bolts without the special tools to remove the locking pin. I’ve seen people get a couple of those bolts out, add your favorite thread locker and reinstall.

Thanks! Yep, LED’s don’t dim in a nice linear scale like incandescent as they use pulse width modulation to dim. I’d be inclined to add a filter to them to lower the overall brightness down to a somewhat stock level. You could also switch the hvac panel to led but it required some additional reflective work to have the led look correct. If the hvac panel and other radio lighting matches, it should look good in the dash. And there’s enough separation between the instrument panel and the center of the dash it should look good.

I’m thinking of picking up the torch with these radios (provided there is no other forum member working on them) and curious to know if there is any interest on refurbished/modified radios. Many options on the table. Bluetooth receiver modules, custom tuning DSP (usb programable), restored lighting and buttons/faceplates. These radios would no longer have any casette decks. I’ve done batch runs of hvac control decks now and custom switch/bezel systems and these would be a good fit along with those other products. Again, this is just a feeler at the moment

Is the headliner board original? If so, I’d be interested

So I’ve deciphered the led lighting upgrade and the foam button backing. Took several attempts with different types of foam to figure out what works, but you’re basically looking for a medium density open cell foam about 1/8” thick. It is nice not to have the buttons rattling around and standing as they should. The led upgrade involves using a T1 or 7219 bulb. The bases are a twist lock but the actual bulbs are a wire wrap design around the base. If you switch to led, make sure you get your polarity correct. Also, when soldering, I’d stick with maybe a 20ish watt iron. I have to cycle my 60w iron on and off to keep the right temp. The 7219 bulbs are also correct for the display backlighting. Changing the display bulbs is a tedious and delicate job. I’ve also sourced switched 12v and 5v reference cables on the casette deck connector. I’m about to build my final configuration radio as I want it for my truck. New button foam, refinished face and buttons, all new incandescent bulbs with a slightly higher wattage than stock, Bluetooth receiver with custom DSP. It will have am/fm and Bluetooth. Could also have an aux input but I don’t feel like fishing down more wires through the dash for that. This radio will look like a NOS unit on the outside with completely custom internals. Here are some pics I took while playing around with different bulb setups and restoring the button backing.

All the glue is dry now. Going to put in some seam sealer around the inside just for the xtra insurance. For reference, I used 1/2” birch, wood glue, 1.25” cabinet screws and polyfill. Will probably finish them with some black textured bedliner. Next, I’ll cutout the b pillars and measure out the cabinet/edge supports

Seriously, try this setup. Excellent performance in the MJ.

Some progress made

So the 90+ calipers are not an upgrade on the front D30 and are not compatible. The 89- knuckles used a bolt on caliper while the 90+ switched to a floating caliper with cast in pad “wings”. The 89- has man my upgrade options depending on the wheel size you have. You need at least 16’s to do anything special. The stock brake setup isn’t bad either, just don’t use hard pad compounds (like pure ceramic). Grab Centric posi-stop pads along with centric rotors and calipers for your model year axle. It’s plenty for a stock ish rig up to about 31’s. Don’t go with drilled or slotted rotors either as your just loosing a bit of pad contact area. Save those for street cars with oversized brakes. Keep the master cylinder stock bore size as well. Even the stock booster will work fine if the vacuum is sufficient at idle.

Just keep in mind that there aren't many subs that can fit under the stock curved base seat mounting frame. Pioneer used have a nifty little unit but they discontinued it. I ran a hideaway 8 for some time but that was under the corbeau seat brackets.

Here is a clarification of the audio signal path for reference: the 7 pin connector between the main board and preamp when viewed from left to right below are as follows: 1. Audio channel output from main board 2. Audio channel output from main board 3. Unknown, but likely a low voltage or reference line - will test to verify 4. tape deck channel output from preamp potentiometer 5. Signal ground 6. Tape deck channel output from preamp potentiometer 7. 12v positive for tape deck door illumination So the switching logic is happening inside the main board. Tape, AM and FM radio are all switched on the main board and sent to the preamp on pins 1 and 2. The tape audio comes into the preamp board first, then goes through a pair of potentiometers to set the signal level first before it’s sent to the main board. Since I’m not using the tape deck so this opens up the ability to loop the tuner input through the tape inputs to attenuate the signal down to reduce/eliminate the bleed through signal. So that would look like pins 1 and 2 out from main board 7 pin connector to tape input L and R inputs on the preamp board. Then disconnect pins 4 and 6 from the main board 7 pin connector and route them to the preamp inputs that correspond to the main board 7 pin connector pins 1 and 2. This would allow you to use the two potentiometers on the preamp to attenuate the level of the tuner. It seems like a small transistor here could solve the issue of the auto switching to the aux inout as well. I’ll investigate that possibility.

Ok, that’s an awesome product!! Very clever solution to a very common problem. Do you know if these would also fit the b pillar trim upper screw hole? The one just above the courtesy light.

My suggestion is to ditch the b pillar speakers and run the Kicker CX 4 channel amp. It’s one of the best bang for buck options out there and is a class AB amp which has a very smooth volume response. The infinity speakers you have don’t need much power as they have fairly high sensitivity (volume output per watt of input). With that 4 channel amp, you bridge the rear two channels to a small sub. For a budget system, I’d go with a 6.5” bazooka behind one of the seats. That pairs well with the front door speakers and will give you excellent bang for buck while taking up little space and fitting nicely behind the seat on the floor. What I can say is, don’t mount any subs to the center rear wall of the MJ. The frequency response there is atrocious and the rear glass will take the vibration. For your door speakers, some sound dampening around them will do wonders for how they sound. For most sub 400w 4 channel amps, they will require at least a 8awg amp kit. This will depend somewhat on amplifier type. Class D will use less power than class AB and so forth. As Derf said, always install the appropriate sized fuse near the battery. As for the B pillar speakers, swapping to a larger speaker back there meets with several issues. First, there is no baffle for the speaker there. You will loose a great deal of frequency response b cause the sound waves from the front and rear of your speaker are colliding all over the place in those b pillars. And since they are out of phase with each other, they cancel each other out. Also, they are behind your seat and throw off the front stereo sound stage. And being behind the seats, only lower frequencies will be able to make it to your ears. Amp: https://www.crutchfield.com/p_20646CX36T/Kicker-46CXA360-4T.html Sub: https://www.crutchfield.com/p_204BT6DVC/Bazooka-BT6024DVC.html There is some simple wiring that will need to be done between the amp and sub the amp is rated for 65w per channel at 4ohms for the fronts and the rear two channels can be bridged into a single 180w 2ohm output which perfectly matches that sub. Kicker even sells a little bass knob for that amp to control the sub gain for those two rear channels.

Sounds like something @boxyjeep might offer. Otherwise, the interior screw assortment from Dorman works very well, granted, there will be several in the kits that isn’t used.

The Dorman GM interior trim screw kits have that screw in their assortment. I bought several of those kits and have been able to use them all around the jeep for trim screws.

Yep, both my 90 and 91 were eliminators with buckets

Here are the originals on my 90. They are the same as my 91 as well. Larger washer than I see on the ones in the pics above.

So I’m going to build out a 2nd version of this radio. Here is the plan: I’ll install a Qualcomm Bluetooth board and an Analog Devices ADAU1701 chip. This radio will have AM/FM tuner, AptX 5.1 Bluetooth and a full DSP. I will tune this DSP for the Comanche cab acoustics in my Tomahawk. I’ll program the DSP to auto switch over to Bluetooth when active and switch back over to radio when not in use. This way I can default back and retain radio functions while absolutely 100% eliminating any radio bleed-through. If I get really ambitious, I’ll configure the “play” button to control the play/pause on the Bluetooth chip since the tape player will be gone. On another note, I have a couple of probably good tape players if anyone wants one. I do want to come up with a better solution for the button feel as well. There is a decent bit of slack. Adding felt to the buttons themselves would indeed make them stand out better but would still leave a decent gap to the actual contact pad on the front panel board. If I find what I’m looking for, it should quiet down the key presses and bring the buttons forward a bit for a better feel.

The ones on my 90 have a captured washer that’s a bit larger than the one in the pic