Time to pull the radiator champ, they block up over time and result in what you have. Its not just Mon-dagos. All cars will eventually do it. There will a bottom hose that feed to the water pump, a top hose that returns from the motor to the Radiator, and a smaller hose that feeds to the overflow bottle, if the trans is funning into the rad then that will need to be dropped as well. you mat be able to get away with only droppin the top and bottom hose, using a bottle of radiator fluch and get the crap out.
Radiators scale up over time. You may want to try some scale remover if the flash does not work. Failing being able to flush the radiator, time to get a new one.
I would think its gonna be full of crap.
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I have a car.