Chrysler Repair: 94 Chrysler New Yorker Overheats, chrysler new yorker, radiator core

Question
Hi,
My Chrysler New Yorker 1994 overheats constantly. We bleed the thermostat, but it is only a temporary fix. It is generally fine on the Interstate, but back roads and particular traffic/red lights, the temp begins to rise. After it gets above 3/4 on the temperature gauge it hemorrhages coolant. We have bled, we have checked the fan wiring. I am at a loss for what the issue might be. Any help you have would be very welcome.

Answer
Hi Jim,
I would wonder about a very basic possibility: the radiator core is partially blocked or the fins are clogged with expernal dirt. Check to see if the two sides of the radiator (the manifolds, basically) are quite different in temperature when the engine is full warmed. If so, then that would imply that flushing the radiator, or if that doesn't fix it, replace it is needed. Try shining a light from behind the radiator while you look through the grille to see if there is any significant impediment to air flow.
It might also be that the pressure cap on the pressure bottle is letting out coolant at too low an internal pressure in the system. So you might want to change out the pressure cap. It shouldn't blow out at 3/4 scale typically, assuming the gauge is accurate.
Roland