Just got done replacing the headgasket. Here's whats new - Flushed the whole system before tearing it down, replaced water pump, heater hoses, temperature sensor. When I filled it back up and started it, didn't seem to take much coolant, got it to take about a gallon. started it, top rad hose never gets pressure, no heat. Gauge reads 210 seems hotter than that and shouldn't the t- stat open before that? it's a new 195. I'm afraid to run it too long and destroy everything I just did. It's a 99' 4.0. The electric fan seems to cycle on and off and not run for very long like it used to. After I shut it off I pulled the top rad hose off and nothing in it. I figured after everything I've done I wouldn't have any probs. I'm running out of ideas. Does this sound like airlock or a new T-stat thats bad? Any thoughts? Thanks.
Charlie

 

I always check a new t-stat on the stove in a pan of water and have found some bad ones. Try leaving the rad cap off while idling and let it warm up, add coolant as needed and replace the rad cap when coolant starts to overflow from the rad. When cool, re-check coolant level in the rad.

 

You've got air in the system. When I replaced my waterpump and thermostat I had to put my XJ on ramps and then fill. The key is to get the front end up at an angle.

 

Wonder what the difference is. I found the XJ to be one of the easiest vehicles to flush and fill/burp, that we've owned. The front of the motor is higher than the back when on level ground so air should migrate to the t-stat housing naturally. Letting it idle with the rad cap off worked perfect. Put the cap back on when it starts to overflow.

 

The burping trick worked, just one thing to add. I took off the heater hose at the T-stat. before I filled it. Man what a difference for filling, I kept adding til some stsrted to come out. put it back on, started it, problem solved. Btw I did put it on ramps too. Thanks.
Charlie