I have had a couple that took a LOONG time to burp. If it gets to 212 and it.s less than 100 degrees ambient you can safely assume that its going to keep going up. It should top off at 204 or so then settle down to 194-203. Maybe try bleeding by taking the tower cap off a few times. One XJ took me like 15 tries to get it burped, but after was fine. Started, bled, warmed up and then cooled off repeat, repeat.

 

I think we have it. 70F outside temp. Ranging from about 199 to 203 steady. Saw 208 steady with A/C on, which seems a bit high, but I'll take it. Though the initial problem almost certainly had to do with the reservoir tank and clogged radiator, I probably had something to do with continuing issues...had the t-stat gasket in front of the t-stat ridge instead of over it...Might have been on backwards too, but didn't take a photo, so not sure. Can't blame that on the last owner.

Now showing some engine and transmission error codes however, which may be contributing to the higher temps...Going to move on to the (new?) engine issues which will hopefully be minor (ha!). Plan is to address the relatively inexpensive issues, then if successful, to replace the transmission.

Getting the engine to operate at the proper temperature was a big milestone. If I can make the engine run reliably, without taking it apart (again), I'll spring for a transmission. If not......

So let me close this thread by saying Thank you to all the good folks who contributed.