Anyone hear of this. This is the leading theory behind my dodges running warm problem.

It has an aluminum radiator that is 7 years old. Shop guy told me (before I told him how old my radiator was) that they typically last 6-8 years before the oxidation that occurs on the inside affects the heat transfer and causes the engine to run warmer.

His story.. just happen to fit the timeline of when my truck started to gradually run warmer and warmer a year ago.

1) Is there any truth to this.

2) Is there any checmical a shop can soak it in and clean it off?

(otherwise.. I'm just buying a new one at $200 OEM or so)

Sounds BS to me. The dissolved O2 in the water will be driven off once the solution is raised above 190*F. Without any O2 in the water how does it oxidize? It may be just a rust coating from the engines iron block coating the radiator. A mild acidic flush will remove it.

I guess my all aluminum Rover V8 would suffer the same fate as your radiator if there was any truth to the science.

maybe he meant outside... would that have a similar effect on its ability to transfer heat?

Just trying to cure the running warm dodge.. and not sure where the problem is. All points to radiator.. but I hate replacing a $200 piece of hardware if it can be fixed for less and last another 5 years.

Cleaning the outside would be easy as hell. I sell products to keep these clean and shiny:
http://www.pirate4x4.com/forum/uploads/bjj1.jpg

We use a compound of Hydrofluoric/Phosphoric/Sulfuric acid. The best thing available to the general public would be a old fashion mag wheel cleaner. Look at the warning part of the label. You may be able to find one with some Hydrofluoric and phosphoric in it , but most likely will be Oxalic Acid.

Aluminium heads can corrode beyond repair and they get the same hot water as the radiator. This is particularly obvious on marine engines because of all the ions in the water.

Originally posted by Old Scout
The dissolved O2 in the water will be driven off once the solution is raised above 190*F. Without any O2 in the water how does it oxidize? It may be just a rust coating from the engines iron block coating the radiator. A mild acidic flush will remove it.




interesting i'm no chemist but it you drive off all of the O2 in water wont you just be left with H (a gas) hence the formula H2O :confused:

:confused:

Originally posted by Chief yelling alot



interesting i'm no chemist but it you drive off all of the O2 in water wont you just be left with H (a gas) hence the formula H2O :confused:


dissolved O2 190F Heat will not break a Molecular Bond!

:p

I doubt it is necessarily oxidation that is taking place, but it could well be silted up with precipitated solids that have formed from the heating/cooling.

While I'm in the same boat as OS with my Rover, I would be overjoyed if a new OEM Rover radiator only cost $200.

Take it to another radiator shop and have them boil it out and see if your flow rates improve.

Originally posted by PTSchram
precipitated solids that have formed .

Come awn Paul you need to talk in Jr high chemistry level for some of the guys here. If dissolved gasses are not understood, how could dissolved solids be understood? :flipoff2:

Originally posted by Old Scout


Come awn Paul you need to talk in Jr high chemistry level for some of the guys here. If dissolved gasses are not understood, how could dissolved solids understood? :flipoff2:

Dissolved solids = Koolaid!:D

DuPont used to (maybe still does?) sell an oxalic acid cooling system flush. It worked well for me. Used to drive a '61 Olds F85 with that 215 cid all-aluminum V8, it lasted over 30 years and never had a serious heating problem. Are you running that pink silicate-free coolant? It doesn't seem to hold up as well as originally claimed.

thanks

maybe this is a bad idea for aluminium but when we got build up in our rads after a few years we would drain it and pour in fresh water with that cascade compleet dishwaser soap (its powerfull stuff it will bleach your pants or whatever) we would pour in a whole bunch and go for an hour drive around the city with some long hulls on hills. when we got back home we would let it settle for a few and then pull the botem rad hose and let it all flush out. Then fill it up agane with water run the engine for 30 seconds and then pull the bothem rad hose. we do this about 5-6 tims. Inside that reater looked an new as the day it was bought :eek: :eek:

Originally posted by Chief yelling alot
maybe this is a bad idea for aluminium but when we got build up in our rads after a few years we would drain it and pour in fresh water with that cascade compleet dishwaser soap (its powerfull stuff it will bleach your pants or whatever) we would pour in a whole bunch and go for an hour drive around the city with some long hulls on hills. when we got back home we would let it settle for a few and then pull the botem rad hose and let it all flush out. Then fill it up agane with water run the engine for 30 seconds and then pull the bothem rad hose. we do this about 5-6 tims. Inside that reater looked an new as the day it was bought :eek: :eek:

I have heard of doing that before in fact lots of times.

Originally posted by Old Scout
Sounds BS to me. The dissolved O2 in the water will be driven off once the solution is raised above 190*F. Without any O2 in the water how does it oxidize? It may be just a rust coating from the engines iron block coating the radiator. A mild acidic flush will remove it.

I guess my all aluminum Rover V8 would suffer the same fate as your radiator if there was any truth to the science.

Old Scout, I don't want to nitpick, but I am very familiar with the dissolved O2 in the water. And generally, you are right that the higher the temperature is, the less dissolved O2 is in the water. However, where is it going to go? If the radiator is pressurized, then the O2 isn't going anywhere. If you overpressurize the radiator, you will vent it into the overflow, that is at a lower temperature and when the system cools down, it should suck the fluid back in that is in the overflow can. You will have some dissolved O2 in that fluid.

Originally posted by orbitcat


Old Scout, I don't want to nitpick, but I am very familiar with the dissolved O2 in the water. And generally, you are right that the higher the temperature is, the less dissolved O2 is in the water. However, where is it going to go? If the radiator is pressurized, then the O2 isn't going anywhere. If you overpressurize the radiator, you will vent it into the overflow, that is at a lower temperature and when the system cools down, it should suck the fluid back in that is in the overflow can. You will have some dissolved O2 in that fluid.

My overflow is closed and pressurized, so it's a matter of system design. My radiator is always flooded with zero air in system. But it's really a mute point because oxidation of aluminum radiator/engine will not be a cause of a loss of the cooling systems ability to exchange heat.