Noticed when I first bought my car a few years back the anti-freeze was a brownish color. The PO had used bars-leak on it at sometime and it ran fine with no problem and minimal smoke on cranking it up so I wasn't worried. Well recently I had it flushed, new anti-freeze, changed the radiator out and still.. dark brown coolant. I wouldn't figure blown head gasket the car has great compression and runs smooth with no loss of power. Im just wondering what could have this anti-freeze a solid brown color?

 

The cooling system is either heavily corroded or it's still dirty.

When you got it flushed was any cleaner used or was the coolant just replaced?

 

No it was cleaned and cleaner run through the system then flushed.

 

I would have to say that the system is still dirty.

You can drain the cooling system (radiator and engine block) and refill with some OTC cleaner like Prestone and distilled water (it's pretty benign) and run it for a few weeks. Then drain out the cleaner (both radiator and block) and flush it with clean water with the drains open.

Close the drains and refill with fresh coolant.

 

You would be amazed how much crud will build up in the coolant passages on a block. Last engine I rebuilt, even using a pressure washer with all the freeze plugs removed, still took about 10 minutes of spraying it directly in the holes for the freeze plugs to get all that crap out.

Even if you flush it and it starts coming out clear, once you start driving it, bumps and just the water circulating will keep dislodging crud.

 

For a good many years the car saw minimal use so that may be the cause of the buildup. Thanks paulo57509 I will try what you suggested.

 

Here's another product that I've tried that works well as a cleaner.

http://www.rmi25.com/

I used it in my old Lumina and it cleans really well. Only problem is you need to run a separate cleaner afterwards. It's hard to skim off all the oily crud that starts floating to the top.

The crud really doesn't float into the overflow. The hose connection at the bottom of the overflow tank gets plugged so the crud coats the radiator side tank.

 

The brown/orange color can be two things.

1. mixed "dexcool" / with 'green' coolant
2. Tap Water (which contains ions such as Mg and K) was used


To fix both:
A: Perform flushing, repeat as necessary, replace parts if they are unflushable (heater core, radiator, hoses, anything in there can all be gunked beyond salvage with brown mud).

B: Use only distilled water and however much of one kind of coolant necessary. In Fl I use 0-15% green coolant. I like to be able to dump it anywhere, or in case it explodes (you know how engines can be) so using 100%distilled allows the freedom of exposure. From a biological point of view this is least damaging to the environment, and it never freezes here.

 

vinegar works really good for flushing a system out and its cheap. every used it to clean out an old dirty coffee pot? same principal. just make sure to flush all the vinegar out when done. refill with antifreeze mix.

 

autozone sells those radiator flush kits that you splice into the heater hose, worked pretty well for me.

They say you can leave the part that's spliced into the hose but it started leaking on me about a month after I put it in. just buy new hose after you flushed it

 

Just use caution with those coolant system cleaners!

Since you have brown water it usually means some dumazz ran water
instead of antifreeze/coolant and the inside of the block and radiator
has severe rust build up. In most cases the freeze plugs are rusted
and the cleaner will remove the crud off the freeze plugs and they
will have rot hole thru them then with the rust crud removed they
will leak and need replacing !

I have seen this many times with cars in warmer climates where
antifreeze/coolant is not used..............

Hate to scare ya so just use caution!

 

It isn't the water causing a problem. Water is inside coolant/antifreeze mix when you buy it. They also sell 50/50 pre-diluted coolants. The water is not the problem, it is IONS in solution which conduct electricity (electrolysis occurs). Pure water does not conduct electricity because it lacks those ions. It is safe to use 100% distilled water in a cooling system, there are no ions, there will be no electrolysis, no trouble.

 

SHEESH!

I have TIME and TIME again the brown sludge water in a abused cooling
system from some dumazz using STRAIGHT TAP WATER!
Over time inside the internal IRON BLOCK passages will get rusty
and transfer this to the water which in turn will deposit RUST
particles thru-out the cooling system. Which again collects on the
freeze plugs and rust them out................

YES
SOME brands of antifreeze/coolant DOES contain water!
Distilled or whatever to boot!
SOME DO NOT contain water and recommend to mix 50-50 WITH
distilled water.................