Seeking advice on a radiator and coolant problem on my 2003 Dodge 1500 Hemi....coolant recently blew out of radiator cap so I drained using plug at bottom of radiator. I refilled with 2 gallons of 50/50 Prestone coolant. Reservoir is full but owners manual says it will take closer to 5 gallons to fill. No matter how much I run it, doesn't seem to draw down reservoir level. I'm thinking I still need to add more coolant...I have not detected any leaks at all and I don't know why it blew out in the first place....Temp guage is reading fine.....any advice is appreciated???

Thanks, GTG

 

5 gallons to fill the rad? No way. 5 gallons to fill the entire cooling system meaning the rad and block and hoses. Yes way.

 

yes your WHOLE cooling system takes 15.4L (16.2 qts.)** (not just the radiator)

 

Radiator Cap or resevoir cap?

I would do more than Drain and Fill.

if I had that much preassure build up, I'd replace both hoses and the Thermostat.

Flush the block with water while hoses are disconnected.

You're radiator cap my be busted. It has a pressure range which opens the line to the reserve tank and sucks in or spits out coolant.

Alos fill radiator with truck running and warm so thermostat is open.

 

even though you drained the rad, there was probably nearly a gallon left in the block unless you pulled the drain plugs at the bottom of the cooling jackets on the side of the block

 

if u drive the truck and the temp goes up ur water pump is out

 

Good Morning GTG,
I am the technical manager at Prestone coolants. If you want to completely change your coolant, you have to remove what are called "block plugs" from the sides of the engine, they are located in the middle of the block below the exhaust manifolds. Hard to get to and hard to get out. Another way to get 90% or so of the coolant out of the engine is to remove the lower rad hose, upper hose, let it drain then use a wet/dry vac on both hoses to suck the old coolant out. Then you will likely be able to get about 4-5 gallons of new coolant to go in there. The reason your cap lifted could be that the spring under the cap is getting weak. You can have this tested at your local auto parts store. Be sure to use some fast orange or simple green cleaner, spray your radiator down and let it sit, then use a garden hose and blow out the fins on your radiator too, they need to be clean to transfer heat. Good luck and if you need further help, I can be reached at jay.buckley@honeywell.com

 

Not saying you are wrong, but for most this isn't something I would reccomend doing. Getting new plugs back in will be nearly impossible. I had a few cars that I unhooked both upper and lower hoses, Placed the lower hose in a bucket and poured fresh antifreeze in the upper hose and let the waterpump do all the work of transferring the fluid. Problem is you need to do it when everything is hot and the t-stat is open and it can get messy.
Other option is to use those adapters and make the garden hose push everything through, but then fresh water is no good for a radiator as the water should be distilled.
The block holds atleast 1.5gal and the heater core prob another gal. or so. Doing a radiator dump only is just like doing a pan drop on a tranny, where there's still fluid in the TQ verter and in the cooling lines. Your only getting 40% of the fluid. This will make your 50kmi intervals shoot right down to 20k intervals due to the old fluid remaining in there and the diluted nature of the 2 gallons you put in with the old fluid. You should buy a coolant guage and see where your at on the cooling/boiling temps.

JiffyLube and Valvoline service stations have radiator flushing stations. Can't be more than $100 to get a service done??, and they flush all the old out and repalce it with new.

 

That is why we use the shop vac in my repair shop, it drains 99% of the coolant without disturbing the hoses or block plugs. I strongly do not recommend going anyplace that uses a powered flushing machine. They usually use a old fashioned generic type green coolant or recycled coolant to do those 100$ flushes. Old silicated coolant is harmfull to the water pump seals in your trucks. Think about it, your truck takes 5 gallons of 50/50 coolant. So you need to buy at least 3 gallons of concentrated coolant at 15$ per gallon for good coolant and then 2.5 gallons of distilled water, then a 2000$ flushing machine, the overhead of the shop and technician. Do you think they are using good quality coolant? Some do and some do not. If you live in a dry wether state where they do not slat the roads, block plugs come out and go in pretty easy. Use teflon thread sealer when you reinstall, they are just simple pipe plugs.
BTW- There is not a single automaker that uses or recommends a "transmission flush". The correct way to service a trans is drop the pan, change the fluid and filter. again, most of the "flushers" out there install incorrect generic fluid.