The fluid in my radiator was brown so I drained it and flushed it. Now I only flushed the radiator out with a hose. I did not flush out the engine at all. I think I should have though. About 10 gallons of water for the radiator Refilled it with coolent and it still seems brown.

I have a new radiator on order thinking that it is rusted on the in side. is there other steps I should have taken before buying a new one?

Also whats the best way to flush out the insides of the engine before I install the new radiator

thanks

 

to effectively flush a radiator, there are a few things that should be done.

1) remove the t-stat... not much will get past it otherwise.

2) remove the block drains (knock sensors).

I don't think that brass or aluminum rads can rust...

you don't mention the year... what vintage?

And don't put "Dex-Cool", the orange stuff, into the engine. It will be ugly. There is no way of removing all residue of the green unless you rebuild the engine and replace all components that come in contact with coolant. If you do use DexCool, it will turn to jelly. icky.

 

What year car and what motor?

Was the antifreeze brown or orange? It could be brown because someone mixed dexcool with regular antifreeze or someone put Bar's leak in it to plug a hole.

I just flushed my '90, had to pull the knock sensor to drain the block. You will have to pull the knock sensor(s) to get all of the coolant out.

 

I wonder what else you filled. The whole cooling system only holds somewhere around 18 quarts. Where do you guess 40 quarts went? Check to see if the old red is leaking??? Neither aluminum radiator cores nor plastic tanks rust. Is there a reason to think you need a new radiator? A professional can flow test it for you to see if any of the tubes are plugged up. If you are determined to replace the radiator (or not), reinstall the old rad for the flushing process. *I* use a Prestone reverse flushing kit. After I flush long enough for the water to run clear, I shut the water off and allow the engine to get hot enough to open the thermostat, then I pull the lower radiator hose to dump all the coolant, water at this point, and start over. I drain the system by pulling the lower hose so that the opening will be large enough to pass any larger debris. I repeat several time. Granted this is overkill, but my rad core is 20 years old and seems, good. My engine runs at about 10* over thermostat temp, while moving, never over 210*. Removing the stat and drain plugs are good viable options. If you do this every two years, your radiator, new or old should have a good long life.

Mixing "green" and Dexcool is ill advised, as expressed above. Only with the most thorough of flushes, drain plugs and all, would *I* consider filling it with the other. Good luck, and...

RACE ON!!!

 

My crazy method of thouroughly cleaning cooling sytem is as follows: I disconnect the upper and lower hoses from the radiator, and allow the radiator to drain. I then proceed to flush the radiator very well by putting the garden hose in the upper hose's opening and letting it run until the water is clear. After that, I reattach the lower hose and fill up the radiator with water. I then start the car and let it run with the upper hose (return hose) hanging over the wheel well (Remove brace attaching hose to alternator and it will work). Once the thermostat opens, It will start spewing water out of the upper hose (Don't let water touch you - it'll be about 200 degrees!!!). I then place the garden hose into the radiator filler neck and let it run slowly to keep up with the flow out of the upper hose. Continue this until the water runs clear. Afterwards I detach the lower hose and flush the radiator again. Then reattach all hoses, add 8 quarts of green antifreeze and fill the rest with water. I run the car at about 2,000 rpms with heater on and continue to fill until she's full. Try to park the car with the nose up higher, air will rise to the radiator to get all air pockets out. Don't forget to remove / scrub and refill recovery tank.

Anyhow, its a longer process, but you really get everything out and truly have fresh coolant / water. Some forum member don't use tap water to refill, they use distilled water (less hard deposits = less contaminants, such as calcium etc.) but I have soft water in my area, so I don't worry to much. I actually took my radiator out and cleaned the outside too. Lots of leaves / dirt accumulate between the radiator and condensor. My car runs at about 203-204 degrees any time I'm driving over 15-20 mph. It'll never go above 222-223 even in traffic (Fan comes on and immediately brings it down to 209).

Hope this helps. Good luck. Pete.