Casting Sand: 6.4 Hemi HD Coolant Filter

[crash68]

Both the 6.4's and Cummins have a rep of plugging heater cores / rads ,and the common denominator seems to be the EGR cooler.

They're also both built in Mexico and the formula for the Mopar Purple Kool-Aid has changed. The EcoDiesel also has an EGR cooler and don't hear issues with the heater core like the HD trucks.

 

[EastWestHemi]

I hear you on the heater core flushing, I have some of the tools to do that job—- need to get the tool that adds air to the flushing water to give it some turbulence to carry out what is probably a pile of sludged coolant stuck in the bottom. I still am getting some heat on driver’s side— hoping I bought myself a little time with the flushing exercise.

I think that it’s cooked coolant mixed with corrosion of metals. The purple dye def separated from the coolant, I don’t think it magically disappeared and probably some of the crap is the dye. The coolant looked like the old HOAT orange from my ‘06 hemi.

This was in every gallon I collected. I stopped collecting the radiator drop after 8 gallons, but collected a gallon on the 16th and it not clear water, and same specks and crap in it.

 

[EdGs]

I hear you on the heater core flushing, I have some of the tools to do that job—- need to get the tool that adds air to the flushing water to give it some turbulence to carry out what is probably a pile of sludged coolant stuck in the bottom. I still am getting some heat on driver’s side— hoping I bought myself a little time with the flushing exercise.

I think that it’s cooked coolant mixed with corrosion of metals. The purple dye def separated from the coolant, I don’t think it magically disappeared and probably some of the crap is the dye. The coolant looked like the old HOAT orange from my ‘06 hemi.View attachment 569528

This was in every gallon I collected. I stopped collecting the radiator drop after 8 gallons, but collected a gallon on the 16th and it not clear water, and same specks and crap in it.

Did you dump and rinse out your reservoir?

Thats where I found the majority of the crud in my 2015 1500 5.7.

 

[HEMIMANN]

Refresh my memory - the expansion tank fills from radiator overflow and drains to the bottom coolant hose?

 

[Sherman Bird]

Refresh my memory - the expansion tank fills from radiator overflow and drains to the bottom coolant hose?

No, the expansion tank is tethered to the pressure system at the lower hose, and the smaller hose is merely to route overflow to the ground. At least it's that way on the 4.7L

 

[HEMIMANN]

No, the expansion tank is tethered to the pressure system at the lower hose, and the smaller hose is merely to route overflow to the ground. At least it's that way on the 4.7L

Thanks, Sherm. Getting old and senile.

Didn't EPA make the expansion tanks pressurized - i.e., no more dumping coolant on the ground?

 

[HEMIMANN]

I wish somebody knew what is going on with Ram (& other?) engine cooling systems precipitating out residue before the "recommended" change interval of 5 years / 150,000 miles.

Are other engines having this problem from other makers? Is the change interval too long for OAT antifreeze additives? It seems to be a problem regardless of cooled egr or not. Could it be they are advertising perfect lab condition change intervals again, akin to the great 25,000 mile oil change interval marketing crap?

 

[crash68]

Didn't EPA make the expansion tanks pressurized - i.e., no more dumping coolant on the ground?

Not sure about the EPA but I believe most vehicles that utilize an EGR cooler use a degas tank which is pressurized.
The relief of those tanks sometimes drop onto to the ground(no overflow tank)

 

[Sherman Bird]

Thanks, Sherm. Getting old and senile.

Didn't EPA make the expansion tanks pressurized - i.e., no more dumping coolant on the ground?

Our Gummit is fickle. Pour antifreeze along the fence to kill weeds and the EPA shows up all armed and John-Wayne-ish. They did that to a guy I once knew, who control weed with old coolant. He pissed off a neighbor who turned him in, and it put him out of business and in the divorce court/ poor house.
Ditto that on motor oil and other nasty things.

But, no one seems to give a darn if oil occupies the center of our roadways where cars drive/ leak. Therefore, the overflow of coolant or leaking transmissions or engine oil/ diff fluid, during driving in traffic overheat isn't regulated; well maybe it is in CalEforny.

So, overflow tubes persist!

 

[HEMIMANN]

Our Gummit is fickle. Pour antifreeze along the fence to kill weeds and the EPA shows up all armed and John-Wayne-ish. They did that to a guy I once knew, who control weed with old coolant. He pissed off a neighbor who turned him in, and it put him out of business and in the divorce court/ poor house.
Ditto that on motor oil and other nasty things.

But, no one seems to give a darn if oil occupies the center of our roadways where cars drive/ leak. Therefore, the overflow of coolant or leaking transmissions or engine oil/ diff fluid, during driving in traffic overheat isn't regulated; well maybe it is in CalEforny.

So, overflow tubes persist!

Did you see EPA was going to go after tire makers for leaving tread residue on roadways? Seriously. Probably not going to happen now.

 

[HEMIMANN]

They're also both built in Mexico and the formula for the Mopar Purple Kool-Aid has changed. The EcoDiesel also has an EGR cooler and don't hear issues with the heater core like the HD trucks.

Well, sure could be too flow restrictive a core, but even so, why are solid precipitates showing up? Something is very wrong here, and we can't quite figure it out. As per hemi tick, no responsible party will be forthcoming, so it's up to us to sleuth and share stories.

I scheduled my HD 6.4L Hemi coolant flush for Monday @ only 3 yrs since I did gravity drain and fill with MOPAR premix. That change was @ 5 yrs and not that many miles. The heat output last spring started fading badly. I haven't driven it too much since due to motorcycling season being here since then.

I bought some RMI-25 super-goo to add to it to try to keep it clean, per you guys.

I'll report back what, if anything, the indie shop found.

 

[mdc1990zr1]

They're also both built in Mexico and the formula for the Mopar Purple Kool-Aid has changed. The EcoDiesel also has an EGR cooler and don't hear issues with the heater core like the HD trucks.

I know FCA went from HOAT orange to OAT purple, but this is the first I’ve heard of the OAT being reformulated

 

[Sherman Bird]

Did you see EPA was going to go after tire makers for leaving tread residue on roadways? Seriously. Probably not going to happen now.

I thimk it's something in the water. Must be!

 

[HEMIMANN]

Time to get on with it while it's motorcycling season.

 

[EdGs]

Refresh my memory - the expansion tank fills from radiator overflow and drains to the bottom coolant hose?

No, the expansion tank is tethered to the pressure system at the lower hose, and the smaller hose is merely to route overflow to the ground. At least it's that way on the 4.7L

The overflow on my '15 Hemi just had the single small hose feeding it from the radiator neck. There also is a spout built into the side of the tank. I found that when rinsing mine out.

On my '02 4.7, the tank is fed from a tee in one of the heater hoses and is pressurized.

 

[Sherman Bird]

The overflow on my '15 Hemi just had the single small hose feeding it from the radiator neck. There also is a spout built into the side of the tank. I found that when rinsing mine out.

On my '02 4.7, the tank is fed from a tee in one of the heater hoses and is pressurized.

Yup! And the location of the pressure cap says it all.

 

[HEMIMANN]

Apparently I caught it just in time, as the sludge started to reduce flow through the heater core. I decided to include the RMI-25 additive with the new MOPAR OAT coolant new.

Thanks to all for posting about this issue (small heater core coolant passages).

From my Indie Shop that did the system flush:
"The majority of the sludge was in the coolant reservoir, while flushing it we did not notice any sludge. The heater core came out good, it had really hot heat, but of course it is summer time. "

 

[EastWestHemi]

Did you dump and rinse out your reservoir?

Thats where I found the majority of the crud in my 2015 1500 5.7.

Yes, hoses off and flushed through the reservoir for 20 minutes…. What was left was not going to unstick from the sides. On the final drop, still producing that small sediment crap. My heat didn’t change on the drivers side, still very weak. I’m going to change my serp. belt, tensioner and pulley, maybe that will help the water pump produce more pressure for the radiator core… although that is probably just wishful thinking.

They probably tested the 6.4 for a year or two way back when, ran the truck all day everyday for thousands of miles and didn’t really give it the thousands of heat cycles and real world conditions a sold truck would see. Don’t think the 10 yr 150k on the coolant is right, but did think that refreshing the system a couple times would do the trick….. it didnt— here I am at 91k miles with a plugged heater core.

 

[HEMIMANN]

Yes, hoses off and flushed through the reservoir for 20 minutes…. What was left was not going to unstick from the sides. On the final drop, still producing that small sediment crap. My heat didn’t change on the drivers side, still very weak. I’m going to change my serp. belt, tensioner and pulley, maybe that will help the water pump produce more pressure for the radiator core… although that is probably just wishful thinking.

They probably tested the 6.4 for a year or two way back when, ran the truck all day everyday for thousands of miles and didn’t really give it the thousands of heat cycles and real world conditions a sold truck would see. Don’t think the 10 yr 150k on the coolant is right, but did think that refreshing the system a couple times would do the trick….. it didnt— here I am at 91k miles with a plugged heater core.

Yeah, my heater core started plugging up @ 65k miles / 8 years, even though I gravity-changed the coolant @ 5 years.

It's not good enough, obviously. I just had it flushed out and added a bottle of RMI-25 in hopes it keeps the gouk suspended. Like others have said, and a new bottle of RMI-25 once a year.

 

[Matt Luken]

Was it "sand-colored" tan? Or was it gray and black particulate?

It was sand. Ive seen casting sand and this is it.