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Has anyone done this on the Hemi? The procedure in the service manual sounds overly and unnecessarily complicated.
I was planning on draining the system, opening the bleed screw, filling the system until coolant oozes out, closing the bleed screw and filling to the top. Then running the engine with heat on and top off until t-stat opens. Close it all up and just keep adding coolant into the overflow over the next few days.
This all was until I saw the service manual, which confused the sh*t out of me. Any thoughts from anyone who's actually done it? TIA
 

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Well, the best is too fully drain the system, flush with fresh water, fully drain the system again, then fill with 50/50 of the "correct" anti-freeze and "distilled" water.

The newer engines and cooling systems get hard to fully drain, but just draining at the radiator plug now-a-days barely gets half the coolant out. That is why there is such a complicated procedure. Especially if you have the rear climate control, you'll have a lot of coolant trapped in the lines and rear heater core.

Opening the bleed port and filling from there is a MUST, you'll get trapped air otherwise and enough trapped air you'll likely overheat before it works it way out of the system.

I do NOT have a Hemi, but have done this on plenty of vehicles and it seems to work well, but you need an air compressor, perhaps improvising with a tube and blowing with your mouth might be enough pressure.

Leave the radiator cap on, drain from the radiator drain, this will form a vacuum and suck all the old coolant out of the overflow tank, once the overflow tank is empty you can pop the radiator cap and it will drain more quickly.

Disconnect the lower radiator hose, NOT sure on the Hemi, but the powertech engines the thermostat is in the neck to the lower radiator hose. I always replace the thermostat with a new one at coolant changes, so I just unbolt the lower neck and pull it to change the thermostat. That will get out a lot of coolant still trapped at the low points and the engine.

I remove a heater hose to the front heater core and use compress air to blow out the coolant in the heater core and the line, doesn't take much presure, you could hook up a hose and probably do this with your lungs alone if you don't have an air compressor. If you have a rear heater, I use a vice grips to clamp off one section of hose to force pressure down the other side of the "T" in the heater hoses and flush out the coolant from the rear lines and heater core.

Finally is the last bit of coolant left in the water jackets in the engine block. Some engines it an extreme pain to pull these and its only the last 5 to 10% of the coolant left trapped in there. So if you blow this off, your still doing good and getting a good amount of new coolant to protect the system in the vehicle. For my 3.7L Commander, I found compressed air sprayed down the bleed port actually forced all the coolant left in at the bottom of the water jacket. Of course I still had the lower neck removed with the thermostat out, so there was little resistance to the wave of coolant created coming out from the compressed air, the thermostat is still in, I doubt anything is going to get past it. Don't know if that will work on the Hemi or the 4.7L V8, but worth a try if you have an air compressor.

Hate to say, I know its a pain, but if you've got rear heat, if you just pull the radiator drain, I'm guessing you're only going to drain less than half the coolant, you're going to have to drain the overflow tank, at least pull lower hoses and blow out the heater lines/cores to get a good 90% or more of it.
 

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Oh, the correct anti-freeze is the HOAT formula for Chrysler/Ford/Mercedes. Thats the dealer anti-freeze, the only aftermarket equivalent that I am aware of is Zerex G-05.

DO NOT USE ANY OF THESE "ALL MAKES, ALL MODELS, MIXES WITH ANY COLOR ANTI-FREEZE", it is a derivate of GM DexCool, they are all rip off's. If you're going to use any other anti-freeze, then use the good old fashion "Original Green" IAT Anti-Freeze and change it every 2 years/30k miles.
 

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Is there a diagram for where the drain and lower hose is located?
Locate the hoses running to the Radiator, there will be two, one on the upper side of the radiator and one on the lower side of the radiator, that run to the engine for circulating the coolant. The hose connected to the lower side of the radiator is the lower radiator hose.


The drain will be on the lower portion of the radiator. If you look at the radiator you'll notice it has a "core" of tubes and fins that the coolant is forced through to cool it, on the ends of that core is the "tanks" that the hoses and pressure cap, drain, etc connect too. The drain will be on lower part of one of the two tanks on the ends of the radiator.


This is rather simple stuff, just look and try to find it, using the logic like the hoses connect the radiator to the engine, I need to find the lower one of the two hoses connecting the engine to the radiator.


If you need a manual or diagram to locate the lower radiator hose and drain, you probably should get someone more experienced to help you or take it to a professional. I'm NOT saying that to be mean, some people are not that mechanically inclined, its nothing to be ashamed of, so if you're having trouble just locating the lower radiator hose and drain, you're just going to have a ton of trouble with the rest of the job that is tougher than that.
 

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In just seeing your response. In actually familiar with where my radiator hoses are and have since then flushed my system. I just have read other posts that stated it would be harder to get all of the coolant out without compressed air. That was my dilemma...that and knowing where to connect a hose to blow by mouth to get the rest of the coolant flowing. I just installed my new radiator and thermostat myself and am trying to make sure its fully flushed.
 

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The heater core has two lines running to it, its just another radiator, so you just have to disconnect one of the hoses and blow into it and it will force the coolant out of the line, the heater core and the return hose. If you do it in reverse of the normal flow shouldn't make any difference.

Where it gets complicated is if you have a rear heater, if you do, you will have a "T" in each hose, the "T" taps off coolant to the rear heater core from the front heater core. I put a pair of vice gribs on the heater hose, just enough pressure to pinch off the hose, first on the hose coming off the "T" leading to the rear heater core (on the same hose I'm blowing out) then once that circuit is blown out, I switch the vice grips to after the "T" to block off the heater core just blown out and redirect the air pressure to the rear heater core.
 
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