pizzaman09

You could definitely stand to tighten the belt some. If I remember the adjustment is on the power steering pump.

Silicone based products like dielectric grease are a bad idea, they are extremely, extremely difficult to clean off and will definitely reduce the friction on the pulleys. That said silicone will at least not damage the belt like hydrocarbon based oils would, so from that perspective it's not the worst choice. Why not just replace the belt? I haven't priced them out but I have to imagine a serpentine belt can be had for under $20.

I did all of mine on the ground from underneath with a variety of wrenches but primarily a ratcheting box end wrench. They were not easy and I have skinny orangutan arms. I could imagine it being a reasonably easy job if you take out the air box from the top. The air box is fairly easy. Also, check to make sure all 6 are there, I was actually missing a stud completely on the back most one.

Photos of 1990 Eliminator seats.

There are also some older school systems and some fancy Snap On stuff that can read the diagnostics ports, but definitely the Renix Engine Monitor is worth its weight in gold. Buy one and you will be delighted by your new found diagnostics capabilities for Renix. Theoretically you can also read voltages off of the diagnostics ports but the REM makes all of that way simpler and reports things out in easy to understand terms.

My 90 Eliminator has the wing back seats in grey cloth with vinyl on the sides and full vinyl headrests.

The manifold leaks probably were not helping you. I happened to tighten my manifold the same time I swapped a crap new Bosch O2 sensor in. So even though my truck stopped stalling, it intermittently ran rough at idle due to it being lean. The O2 sensor was super slow to react. When I got my REM, I realized this and bought a good NTK, which instantly fixed the problem and allowed the engine to run super smooth at idle as it was not going very lean for extended periods of time. My point is, what is the condition of your O2 sensor? Could it be damaged? Vibration from a hammer or some other unfortunate hit can ruin an O2 sensor, they are fragile.

Get the largest one that fits. My 90 4.0L with AC came from the factory with a 100 amp alternator. The power windows and locks shouldn't take much power, but the AC can be power hungry.

The 89 and 90 models are a bump up to 182 hp. I'm not sure which ECU you have as I'm no expert in it but people tend to like the upgrade if you have an ECU from an 87 or 88.

Mine feels like the way you describe yours around some turns. Also if there is a decent load in the bed or I'm hauling a heavy trailer the diff or something in the drivetrain gets grumbly or the tires scrape. My LSD is a clutch based one and I can't imagine is very strong at 270k miles

Do you have an LSD rear end? My truck with a Dana 44 with LSD definitely isn't the happiest in the truns like you describe. I haven't the checked the quality of the fluid but know it has it.

It's easy enough to try to tighten each bolt and you'll see if it helps. When I did mine, I found that the back bottom stud had backed out of the block and was missing, all of the nuts were loose. I have yet to change the gasket and I think it does leak some but doesn't effect the way it seems to run.

Mine was sucking in air at the slave cylinder, hence all it took was cracking the slave bleeder for 5 seconds until the stream of fluid didn't have bubbles. However mine never came back after going soft like you are describing. It is possible that you are getting air at the master and then it is bubbling back up into the reservoir. That said usually it is the slave that goes bad.

The harmonic balancer looked like it was ready to be replaced.

I'm personally a fan of Cruiser's suggestion of Oxgard. It is basically silicone grease with carbon black in it to make it electrically conductive. So the silicone grease keeps moisture and corrosion out while the carbon black allows a better electrical contact to be maintained than if straight silicone grease (dielectric grease) where used. Sure you could paint over it too, but paint isn't necessary a great way to seal a connection, particularly one that can vibrate.

I would start with cleaning all of the contacts with the bulbs if it previously worked correctly. Then contacts with the switches. Followed by all of Cruiser54's tips for the electrical system.

It did hurt, but I'm glad it didn't end up in a landfill at least. I'm happy when people can recycle. I listed it here for free for months and eventually on Facebook marketplace.

Aw, I didn't notice that detail. External slaves are just nice as they are more accessible for when they need servicing. Plus it seems that the external slave cylinders are better quality. It helps that they have less internal seals.

Looks like you are doing a fine job! I did the advanced adapters external slave swap on my 90 Eliminator, possibly the best improvement I have made to the truck. I did not change the master and I believe I should have as the clutch is about twice as heavy as it used to be. Something about there being a different master part number for the external slave cylinder Jeeps...

When I bought my truck, the slave cylinder would suck in air, the pedal would get softer and softer until it just couldn't disengage. For a while it was manageable, once very few months I would bleed it. However it got to the point of every week and then ever quicker. Being that I have an AX-15, I did the external slave swap. You have a Peugeot transmission so that isn't a direct option. If you want to learn to bleed the clutch easily, just fill the master cylinder, crack open the slave bleeder, and let it gravity bleed. Let it bleed until the stream is constant. Close the bleeder, top off the fluid in the master and it will be nice and firm. I wish you luck, finding a quality internal slave cylinder now a days.

Well done. I also recommend Cruisers tips of using Oxgard on connections where it makes sense. It protects the connections from oxidation and maintains conductivity.

Let us know what you ultimately choose and how it rides.

You might get away with just the carpet if I'm interpreting the photo correctly.

I do agree that this sounds like a vacuum leak. A smoke test will prevent you from chasing your tail. It is worth checking the header bolts, make sure they are tight.

Spray some near the header while at it, particularly near the back of the engine.