I just bought a 2000 xj sport last night and noticed that the engine bay seemed really hot. The gauge on the dash said it was at 210 which I understand is the proper temp. Is it possible I am getting a false reading?

 

Yes, it's possible you are getting a false reading. But the engine bay on these things is normally very hot. Surprisingly hot, in fact, even when everything is okay.

A decent IR thermometer will tell you for sure.

Since you have a 2000, you have to be extra careful about overheating. There is a well-known casting flaw in the head, and they are prone to cracking. Most don't, but it is a known risk with the 2000 and 2001s.

 

What tempature is too hot? Should I look at replacing the water pump and thermometer? Thank you for the advice

 

Just to give an example of how possible it is: on my XJ the temp gauge works normally up to 210 and then stops right there. I first noticed the issue when the electric fan started kicking on sitting in traffic and the gauge was still pointing straight at 210.

I connected a Scan Gauge II to the OBD II port and confirmed the sensor was reporting correctly and the e-fan was coming on at 223F. I have yet to dig in to figure out the problem with the gauge in the the dash. I just keep the SGII hooked up full time to monitor temp.

 

Point an IR thermometer at the thermostat housing it should read very close to what is on the temp gauge.

 

^^^ this

 

First thing is to buy, borrow, or rent a good IR gun. Someone posted here recently that the Harbor Freight $20 unit can be as much as 15 degrees off, so that's no help.

Someone else posted that he had found that the dash gauge almost acts like an idiot light past 210. Stays there until it's TOO HOT, then spikes up. Like Superslow's post above, he verified that with a scan tool.

210 is where they are made to run, and at that temp, the engine bay is blisteringly hot. It just seems to be its normal condition.

I have read (but have not verified myself) that you can replace pretty much the entire cooling system for around $200, which is not bad (assuming you do the labor, of course). That's radiator, hoses, pump, fan clutch, t-stat, and temp sender. It's not a bad idea with a 2000.

But the first thing is to verify that temperature.

 

If you have an Android phone, you can get a bluetooth OBDII adapter ($15 to $30) and the Torque app ($6) and use it for real time (or close to it) monitoring of the various sensors. It will read out the actual temp the sensor is reading in numbers, which is kind of handy. When my fan clutch died, I could watch it go up, up, up then down, down, down as I moved from red light to red light.

Here's what the Torque dashboard looks like in my Subaru. I usually run it full time in my Subaru, with the added benefit that I can read and clear trouble codes and monitor my emissions readiness at any time.

 

I really like my OBDLink. I had one of those cheapos and Torque, and I could never get Torque to save any logs. The "support" forum is worse than a joke.

My OBDLink died about 5 days before the warranty ran out, and they sent me a new one, no questions asked.

 

I have two of those, the LX (green) and the MX (black). I never mention it, however, because Jeepers are generally cheap bastards who would balk at the $60 (green) or $100 (black) those cost when the $25 BAFX or something similar will usually work okay. But I do agree that those are fine products that work really well right out of the box. Plus you can also use ScanTool's software without worrying about loading a bunch of viruses on your laptop.