Chrysler Repair: 1988 2.2/2.5L engine running hot, electric cooling fan, radiator cap

Question
"HI, I HAVE BEEN UNABLE TO FIGURE OUT WHY MY 1988 LEBARON TURBO 1 GTC COUPE RUNS AT ERRATIC TEMPS WHEN I USE THE HVAC SYSTEM.I BELIEVE THE THERMOSTAT, WATER PUMP AND ELECTRIC COOLING FAN ARE FUNCTIONING CORRECTLY. I SUSPECT INSUFFICIENT FLOW IS THE PROBLEM BUT, NOT SURE IF PROBLEM COULD BE WITH WATER VALVE, HEATER CORE OR AN AIR POCKET.
I WOULD APPRECIATE AN EXPERT'S BEST GUESS. THANX, MKB"


Answer
Hi Mike,
On the 2.2 and 2.5L 4 cyl engine you have to refill the coolant in a way that avoids an air bubble in the thermostat housing. You will see on the top of the thermostat box that there is an allen head plug (6mm I believe) and so you need to drain down some coolant, maybe a quart or two so that the level in the system is below that housing. Then remove the top plug and refill the system through the radiator cap opening until the coolant rises to the level of the top of the box. Then put some anti-seize compound on the threads of the plug and put it back in the hole. Then finish refilling the system. Note: before you even drain the system start the engine and turn on the heater to make sure the water valve to the heater loop is open. Then shut off the engine and begin the partial drain down as described.
That may well take care of your problem.
Roland
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