my brother has a 1990 k5 blazer and it has a radiator and its full of fluid, but the coolant take is bone dry? do we need to wash it out and add coolant before something bad happens?
sorry if its a stupid question, i dont know much about these old trucks

 

Every car needs coolant. simple as that. I would add some asap

 

if youre talking about the little plastic bottle off to the side, thats called a overflow bottle, itll suck fluid out of there when needed or catch fluid if the engine over heats. fill it up to the "full" line on it and youll be all good

 

thats what im talking about, thanks!