You may want to check your model year. There is no such thing as a 1990 Durango.
Drain the water from your 1990 Chevy Corsica cooling system. Remove the heater core water supply hoses. Remove the heater core retaining bolts. Reverse the process to install the new heater core.
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very carefully
Remove the water supply lines from your 1990 Ford E3 50 heater core. Remove the heater core retaining bolts. Reverse the process to install your new heater core.
Where is the Water Pump located and how do you replace it on a 1990 Chevy Corsica?
comes out inside . remove glovebox and go in that way . about one hour .
You pretty much have to remove the entire heater box under the dash on the passenger side
How do you replace a waterpump on a 1990 BMW 325i
To replace the heater core on a 1990 Chevy Caprice, begin by disconnecting the negative battery cable and draining the coolant. Remove the dashboard and any components obstructing access to the heater core, such as the center console and the climate control housing. Disconnect the heater core hoses from the engine bay, then unbolt the heater core from the housing and replace it with the new unit. Reassemble everything in reverse order, refill the coolant, and check for leaks.
I've been trying to figure out the same thing.
Take out the whole dash and then the heater core should be behind the glove box on the passenger side.
sell the car