Its a 50/50, ive never used clr in that kind of instance. I didnt like its performance on the household chores But if it works, hell worth a shot.

 

Well you have aluminum in the motor and I think it eats it. One problem I also see is that things could detach and end up in your radiator or core.


I don't know about the idea?

 

We are talking about isolating just the heater core and chem flushing, no engine involvement. If the heatercore replacement was already in the plans, testing a little before commiting $400+ on a core wont hurt. He knows that the HC must be flushed and neutralize with baking soda to remove all the chems so it would never get to the engine. CLR is a little caustic, but as some mentioned take a piece of foil, put it in a dish, let it sit. 20 minutes to 2 hours nothing would happed

 

Makes sense. Give it a try!

 

dumb azz noob question but what about plain 'ol vinegar to flush the core, if it works for clearing hard water deposits out of my shower head wouldn't it do the same for the HC?

 

How are you going to get the vinegar to the core? You going to run it through the entire motor via the radiator?