1998 chevy Blazer LS
The heater didn`t work so I flushed the heater core with just plain water.
The heater blew hot air for about 3 or 4 minutes than stopped.
I flushed it again with water and it worked for about 5 minutes then stopped again.
I flushed it a 3rd time using CLR,then plain water it worked for about 10 minutes than blew cold again.
i figured that there must be crap in the radiator that was circulating and blocking the heater core so i got some gunk brand radiator flush and poured that in the radiator.
It said to leave it in for 15 minutes and then drain and flush the radiator with water.
I poured it in when i was at the store and drove 30 minutes home, by the time i got home it was dark, so my question is will it hurt to leave it in the radiator until tomorrow?
If the gunk radiator flush doesn`t work would it hurt to put CLR in the radiator and run the engine for 5 minutes or so?