1985 Chevy blazer 4wd over heated and radiator fluid came in the cab Is it the water pump?
Heater core blew, but you need to find the reason why, it could be a blown head gasket causing too much pressure in the cooling system, you might want to check your radiator also.
And the third strike .... HEATER CORE ... your out!
Ultra slim chance the hose on the other side off the firewall ... but unless your seriously due for some good luck it's the core.
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