Heater core flushing 2016 Hemi 6.4 2500

[EastWestHemi]

Finally got around to flushing my heater core. Was having really poor heating performance, especially on driver’s side.

Flushed both directions with hot water from sink— 120 degrees for 1.5 hour. I bought the gun that allows you to inject air along with the water. Switched back
And forth 10 times each way, let my compressor build to 30 psi and flushed and pumped the air to it— each direction 10-12 minutes. Would give it short 1/2 second bursts, and then when the compressor would get down below 10 psi give it 3-4 second bursts. Don’t even bother doing this exercise without the air assist, the only time it produced the sediment was during the air injection.

Glassy orange flakes, glassy black flakes, orange “dust” is what I found. See pics. The black flakes were quite a surprise, looks like carbon.

Heat is pumping hot now… no dealer $2700 bill or having to spend 10-20 hours doing the heater core myself. I was careful to not overpressurize the heater core.

 

[EastWestHemi]

Definitely didn’t flush everything out, but it was producing 95% less sediment towards the end even with more aggressive air injection— I would catch the water into my cup to check during the air spurts.

 

[dieselscout80]

Sounds like you got it cleaned out.

Got a link to the system that you used.

 

[HEMIMANN]

View attachment 575696View attachment 575697View attachment 575698View attachment 575699View attachment 575700View attachment 575701Finally got around to flushing my heater core. Was having really poor heating performance, especially on driver’s side.

Flushed both directions with hot water from sink— 120 degrees for 1.5 hour. I bought the gun that allows you to inject air along with the water. Switched back
And forth 10 times each way, let my compressor build to 30 psi and flushed and pumped the air to it— each direction 10-12 minutes. Would give it short 1/2 second bursts, and then when the compressor would get down below 10 psi give it 3-4 second bursts. Don’t even bother doing this exercise without the air assist, the only time it produced the sediment was during the air injection.

Glassy orange flakes, glassy black flakes, orange “dust” is what I found. See pics. The black flakes were quite a surprise, looks like carbon.

Heat is pumping hot now… no dealer $2700 bill or having to spend 10-20 hours doing the heater core myself. I was careful to not overpressurize the heater core.

How many miles and years?

 

[EastWestHemi]

92,400 miles, 2016, I dropped the coolant in the radiator twice for partial refresh at 15k and 40k. My truck has high idle though, 3000 driving and 1200 idling… so 92k miles is probably more like 120-130k considering idling.

I did a full flushing at 90k, dropped the radiator and added distilled water 10-12 times until I was 99.9% water, and then added concentrate back until I’m 50-50. The heat was already faltering, the whole flushing procedure made it worse.

Amazon.com: Cooling System Flush Gun : Automotive

Buy Cooling System Flush Gun: Cooling & Water Pump Tools - Amazon.com ✓ FREE DELIVERY possible on eligible purchases

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[EastWestHemi]

Saw one of the hoses from heater core goes into the oil filter cooler, maybe that black carbon comes from the oil cooler? Or possibly some carbon bleed by the head gasket?

 

[EastWestHemi]

Driving it right now, heat is burning my face it’s so hot

 

[HEMIMANN]

92,400 miles, 2016, I dropped the coolant in the radiator twice for partial refresh at 15k and 40k. My truck has high idle though, 3000 driving and 1200 idling… so 92k miles is probably more like 120-130k considering idling.

I did a full flushing at 90k, dropped the radiator and added distilled water 10-12 times until I was 99.9% water, and then added concentrate back until I’m 50-50. The heat was already faltering, the whole flushing procedure made it worse.

Amazon.com: Cooling System Flush Gun : Automotive

Buy Cooling System Flush Gun: Cooling & Water Pump Tools - Amazon.com ✓ FREE DELIVERY possible on eligible purchases

www.amazon.com

Yeah, and the coolant circulates through the exhaust-to-coolant EGR heat exchanger exclusive to the 6.4 Hemi, adding further heat and flow restriction to the cooling system. It's just a poorly-designed cooling system. They cheaped out on heat exchanger core size. I could have forgone sodium-filled exhaust valves for a cooling system that didn't plug!!!