Big Job and even bigger if you have AC. If you intend on DIY, purchase a shop manual for that vehicle, you will need it.
how to replace a heater core in a 1997 Chevy blazer
how do i replace a heater core in a 2001 Chevrolet blazer
How do you replace a heater core in a 1998 Ford Expedition?"
How do you replace a heater core in a 1998 ford expedition?"
with your hands
Drain the water from your 1994 Chevrolet Blazer cooling system. Remove the heater core water supply hoses. Remove the heater core retaining bolts. Reverse the process to install the new heater core.
how do you get to it
Check coolant level .Then thermostat . Then hearter core
You can but you still won't be able to get it out.
Take it to a mechanic and say "will you fix the heater core?"
Remove the water supply hoses to your 1998 Chevy Lumina heater core. Remove the heater core retaining bolts. Reverse the procedure to install the new heater core.
your heater core is going out, you need to replace it before it ruptures.