Not trying to be rude TSM but most of the time in the screen the upper right hand corner has something like this ( Jan 2014 ). I have such a dislike for reviving old threads I really make an effort to avoid them.
As a side note it seems most forums just let threads continue to lurch around like Zombies.
Whatâs the harm of old threads? People search the site for a specific issue, find it, read it and jump in with their issues. Itâs not as if the problems keep changing over the years, making the information obsolete. A heater core is a heater core, and the basic principle hasnât changed in my lifetime. Mostly they are just harder and harder to get to.
I completely agree. I see no real harm in old threads if the discussion can still be relevant to someone. Perhaps the OP has long since moved on, but us gearheads can still share ideas that may help someone.
I thought you werenât supposed to use CLR on aluminum products?
Most heater cores nowadays are aluminum . . .
I just swapped my heater core intake and output tubes to flush a blockage and it worked very well. The downside is that the circumstances indicate that most of my cooling system needs to be replaced.
I thought using the premium antifreeze would let me go longer between changes, but I developed a pinhole leak near the radiator drain plug. It wasnât a problem until last Thursday when something that looked for all the world like tissue paper pulp broke the pressure seal at the radiator cap. Unbeknownst to me I lost about a gallon of coolant while at work. Temp had dropped outside and the lack of radiator heat tipped me off before the engine temp got too high.
I opted to use one of the leading brands of leak stopper additives, which did help the leak. Unfortunately two days after re-equilibrating the system I was no longer getting heat out of the passenger side registers. Checked the mixer and indoor/outdoor actuators and they were good. Got heat back after flushing the radiator and swapping heater coil lines, but I had to get on the highway and take it over 4K rpm for a bit to flush everything out.
Point of the story is that the water pump needs replacing. Corrosion was what caused the leak in the first place, and secondarily to worn out pump allowed the fix-it funk to languish the heater coil and block most of the transverse flow.
If the heater core flow direction is reversed, wouldnât that just flush the debris that has accumulated in the heater into the rest of the cooling system. When folks here say theyâve reversed flush the heater core, they usually mean with a garden hose hose, and the outlet with the gunk from the heater core drains into a bucket for disposal, when the engine isnât running