: Coolant Sludge!!!!!

08-16-11, 12:37 AM
hey so today i decided to check all my fluids and everything because my car seems to be running hot. i have no temp lights or check engine lights but it seems hotter than usual. well i get to the radiator and open the cap and see a faint milky substance. now my previous experience with this was with my 99 sts that had a head gasket leak. but with that coolant was going into the oil not the other way around. now i do see alot of nasty gunky brown residue on the radiator cap as well as in the reservoir also. im thinking that maybe it just needs a really good flush and im hoping its not the HG. any help or suggestions would be a great help.

08-16-11, 12:43 AM
Have you ever used any leak stop products in the cooling system? When is the last time the coolant was changed?

08-16-11, 12:49 AM
no i havent used anything and ive had the car about 6mo and i havent do a flush or change

08-16-11, 12:51 AM
I would change it immediately.

08-16-11, 01:02 AM
ok now my next question is, is this a holy shit do not pass go type thing or do i a little time?

08-16-11, 02:09 AM
Ok, let me rephrase that: I would change it as soon as possible, flush it (in this case a chemical flush would do a world of good) and replace the thermostat.

Your car has an iron block, LOTS of corrosion happens once the coolant looses it's anti corrosive properties. Coolant passages, the heater core, and the radiator can become clogged (both partially and completely), the thermostat can become stuck, or sticky enough to not open completely. Any of those things could be causing your car to run hotter than normal.

08-16-11, 07:55 AM
my 87 gets some sludge build up in the coolant reservoir too. I had planned on doing the water pump, thermostat, and a good chemical flush this summer but then it got in an accident so I haven't been able to work on it.

I've done chemical flushes on it in the past and that didn't stop the sludge from returning. :(

08-16-11, 10:44 AM
Something to consider:


08-16-11, 10:51 AM
that's awesome! anyone use one of those things? are they worth using?

08-16-11, 11:57 AM
I've seen 2 in use in iron block engines, they do collect a fair amount of debris quicker than I would have thought.

08-16-11, 08:17 PM
Do you think it's rust or Bars Leak? Bars Leak is a golden brown sludge. I leave the green anti freeze in my cars for a few years at a time and never seem to get any sludge. In any event it is good to change fluids when you buy a new car.