From the factory, the only switch between 12v power and your headlights is the headlight switch. There's no signal switch, or relay. It's a really crappy setup and limits voltage terribly. The most likely cause is your headlight switch itself. Try removing the switch and you'll more than likely see some scorching of the pins. After you replace the switch (once you've confirmed it IS the switch), upgrade to the Putco headlight relay harness https://smile.amazon.com/Putco-23000...2Aentries%2A=0 or the headlight harness sold by a user on here (of much higher quality) https://www.cherokeeforum.com/f74/he...pgrade-219596/

This will not only increase power output to the headlight, but it will also take voltage load off the headlight switch itself.

 

Nevermind. Got this solved. It was a 7/8-14 shaft with some smashed threads. 3 hours of filing the threads, the nut went on.

 

Ouch! Kudos on the perseverance though.

 

On the trip back to nola yesterday my ac stopped blowing cold. I figured I was just low on freon but at some point the compressor started making noise.
Here is a video
[YouTube]6xuFaMFOpGU[/Youtube]
https://youtu.be/6xuFaMFOpGU
The clutch goes in and out a great deal and a puff of smoke shoots out right when it engages.
Will a clutch kit fix this or am I going to have to sell a lot of belongings?

Good Lord have mercy, I can never remember the different ways various sites embed videos

 

Might be a shim issue:
http://www.jeepforum.com/forum/f11/c...stion-1231254/

 

I sure hope it's as easy a fix as that.

 

Also check to see if you can rotate the compressor by hand, it might be seized up. Grab the center part of the clutch assembly and turn in the normal direction of rotation. There will be some resistance but it should turn smoothly.

 

I was able to turn it by hand but it was plenty gritty. Made it to church but it got much worse. Ended up getting a bypass pully until I get another compressor or rebuild this one if possible.
Is there a reliable way to keep moisture and debris out of the ac fitting? For now I just taped and zip tied a sandwich bag around it but I know that's not doing much to keep undesirable stuff out of my ac system until I can get it back up again.

 

If it makes you feel any better it cost less that $200 for me to do the ac compressor, expansion valve and drier on my Jetta after a couple tools rented from a parts store and a few YouTube videos.

 

The biggest problem is that when a compressor fails internally it tends to send metal shards into the AC system. If left in there this will ruin the new compressor.

So you'll need to flush the system out, but the parallel-flow condensers used in R134 systems are a problem. If metal shards are lodged in there it's likely the flushing compound will just route around them. Then later they can come loose to create havoc. So the safe thing to do is replace the condenser. Ditto for the evaporator if it is parallel-flow. (Not sure if that's the case on the XJ.) Of course you would also need a new drier but that's going to be the case whenever doing major work on the AC system.

 

Thank you, I'm thinking it won't be too expensive in the end

Is there a way to tell if things went bad internally. I think that it was just my clutch and bearings that went out. If so, is it worth just replacing those or just get a new compressor?

 

Personally I'd get a new/refurbished compressor.

 

Have been wrestling with bad cold starting (doing the poor man's prime) and based on what I'd learned here, decided to replace the fuel pressure regulator, and did the fuel pump and filter while I was at it. Sadly, no real improvement. What's next? Check for a leaky injector? Already replaced the IAC.

 

The clutch plate is keyed and bolted to the compressor crankshaft so it should turn smoothly by hand even if the clutch pulley bearing is bad. So if it's grinding and catching when you turn that clutch plate chances are the compressor is damaged internally. (I guess to verify you could remove the clutch assembly and turn the crank directly.)

You would check the clutch pulley bearing by removing the belt and freewheel spinning the pulley, checking for any looseness, noise, or roughness.

 

So I have this sneaking suspicion that my head gasket is leaking, but I'm not sure. It's a 98 with the original 4.0 engine. 230k on the drivetrain.

Here are some data points:
There does not appear to be any oil in my coolant or coolant in my oil.
I'm not mysteriously losing coolant (that I can tell).
Fan clutch replaced last year--temps creeping up at idle, clutch tested bad.
Water pump replaced this summer--metal flakes were in my coolant.
3" lift, 32" tires, stock gears.
Bumper, winch, and light bar hanging off the front:


So here's what I'm seeing. When the ambient temperature is high-ish, like the 90F it was yesterday afternoon, my temps creep up in the 240-245 range when I'm going at highway speeds. I'm fine at lower speeds in that heat, or at highway speeds when the ambient temperature is lower (it was 70F this morning and it was fine).

I monitor my temperatures with a ScanGauge because the instrument cluster is a dirty liar.

While I was researching something else, I came across someone who said that overheating at highway speeds but not at idle can indicate a head gasket problem.

But I wonder---would ambient temperatures really have that much of an effect if I was overheating due to a blown head gasket? Or could it be something else?

I'm borrowing a compression test kit for the weekend to try to get that done.