Hello
with your engine running at 210-200 it is in the normal range for your Jeep, this is the Jeep description
CAUTION: Do not operate an engine without a thermostat, except for servicing or testing.
A pellet-type thermostat controls the operating temperature of the engine by controlling the amount of coolant flow to the radiator. On all engines the thermostat is closed below 195°F (90°C) Above this temperature, coolant is allowed to flow to the radiator. This provides quick engine warm-up and overall temperature control.
An arrow plus the word UP is stamped on the front flange next to the air bleed. The words TO RAD are stamped on one arm of the thermostat. They indicate the proper installed position.
The same thermostat is used for winter and summer seasons. An engine should not be operated without a thermostat, except for servicing or testing. Operating without a thermostat or a low temp thermostat causes other problems. These are: A 'check engine' light and a DTC will eventually be set, longer engine warm-up time, unreliable warm-up performance, increased exhaust emissions and crankcase condensation. This condensation can result in sludge formation
The main problem with your model jeep is the colling electric cooling fan and relay, they are not very reliable, on the 2000 the fans have a tendency to seize and or spin slow so when you start to go beyond the 220 mark the extra colling you need is just not there, be sure to check the electric fan operation
Also the coolant overflow bottle cracks internally allowing the system to pull in air when shut off and cooling down, causing the coolant to aerate and cause corrosion in the block and head, restricting the size of the passages, Normally we replace these in the shop since there is no way to see the crack
Be sure to check the engine control system and fuel systems, if the Jeep is running lean or having preignition problems this can also cause a piston to burn
I hope that this helps you
If you need more information just let me know
Thank you
Donny
So with the factory correct thermostat and radiator the Jeep should run around 210-220 this is where we normally see them perform
ASE Certified Technician
A.S.E. Master Technician, Over 25 years working in Chrysler dealers, Top tech DaimlerChrysler 1998
Thats good to hear, any time you need anything just let me know