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Brown Slime In Coolant!!!
Thread Starter
Teching In
Joined: Nov 2007
Posts: 1
Likes: 0
From: National City, CA
Brown Slime In Coolant!!! I've had this 1999 Camaro SS for 4 years now. I do all maintenance/ repairs myself. No Mechanic has touched this thing since I have owned it. Runs beautiful.
Here's the odd thing. I decide to take the radiator cap off today for maybe the third time since I've owned it. (the only thing I didn't regularly check) I'm thinking of doing a flush on it......I notice this brown slime all over the inside of the cap. Alot of it. I run my finger along the inside of the radiator.......there is more stuck to the top. Alot of it. It has the consistancy of jell-o. Smooth, not gritty, and it breaks off smoothly as I rub in between my fingers. There are also fine chunks of this stuff on my plastic coolant dipstick.
I have read that this stuff could be rust, automatic transmission fluid (I have an auto) , engine oil, or gasket material.
I checked all of my fluids.....
I am full on engine oil. it looks clean and is not foamy.
I am full on automatic transmission fluid. It does not appear to have water/radiator fluid in it.
It does not appear to be gasket material
I am not having any cooling problems
There does not appear to be much on an aluminum block engine to rust that much.
WHAT THE HELL IS THIS CRAP? It almost seems like some liquid gasket material, and if I didn't know better, I would say that it was supposed to be there.
Here's the odd thing. I decide to take the radiator cap off today for maybe the third time since I've owned it. (the only thing I didn't regularly check) I'm thinking of doing a flush on it......I notice this brown slime all over the inside of the cap. Alot of it. I run my finger along the inside of the radiator.......there is more stuck to the top. Alot of it. It has the consistancy of jell-o. Smooth, not gritty, and it breaks off smoothly as I rub in between my fingers. There are also fine chunks of this stuff on my plastic coolant dipstick.
I have read that this stuff could be rust, automatic transmission fluid (I have an auto) , engine oil, or gasket material.
I checked all of my fluids.....
I am full on engine oil. it looks clean and is not foamy.
I am full on automatic transmission fluid. It does not appear to have water/radiator fluid in it.
It does not appear to be gasket material
I am not having any cooling problems
There does not appear to be much on an aluminum block engine to rust that much.
WHAT THE HELL IS THIS CRAP? It almost seems like some liquid gasket material, and if I didn't know better, I would say that it was supposed to be there.
Are you guys running the "extended life" coolant, or just the regular coolant? That extended life, 100,000 mile "Death-cool" coolant is known to gum up cooling systems and muck them up really well.
If you guys are already running regular coolant then I don't know what's up. If you're running death-cool I'd drain, flush and fill with regular coolant as soon as possible...
If you guys are already running regular coolant then I don't know what's up. If you're running death-cool I'd drain, flush and fill with regular coolant as soon as possible...
ive heard of head gaskets leaking oil into the coolent without coolent actually getting into the engine oil... and that mix makes a nice brown pudding. its possible you have a small head gasket leak and thats whats happening. radiator shops can test your coolent and tell you if theres outside substances in it. i think thatd be your best bet
Joined: Nov 2003
Posts: 6,216
Likes: 236
From: Wichita KS / Rancho San Diego
It's broken down Dexcool coolant. The stuff breaks down if the cooling system is ignored for too long. Get your cooling system flushed out and filled with fresh coolant.
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But... I only had the breakdown accumlated on the bottom of my pressure cap - never on my dipstick. The breakdown deposits were more of a curiosity. The power steering fluid is much more alarming and looked like alien slime all over the dipstick.
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I bought my 00 WS6 with 66K miles. It has green coolant when I bought it and it also had this sludge in it. At first I thought it was oil and took it in several times under warrantee to fix it. It still came back after several flushes. I thought it was oil also. The mechanic at the dealership took a sample and sent it off before tearing into my engine.
Turns out it was ALUMINUM. We never found out why.
Turns out it was ALUMINUM. We never found out why.
I had a PS cooler leak PS fluid into the cooling system. Go to autozone and get the loaner cooling system pressure tester. pressurize the cooilng system and look for bubbles in the PS resevoir. PS fluid in the cooling system also gunked up my coolant level sensor and caused a false coolant level low light to come on. Its all easy to fix.
TECH Regular
Joined: Feb 2005
Posts: 400
Likes: 2
my LT1 had the same brown slime in the recovery reservoir and the coolant dipstick but it hasn't come back since I flushed the cooling system. Whatever it was, the stuff was greasy to the touch so it had to be petroleum based.
I have this same problem!! and no it wasnt the PS cooler like everyone says. Head gasket. But I would By pass the ps cooler with splices and clamps from home depot for 10 bucks, and if it fixes it then its a PS cooler. They only came on the ws6/SS
I have an 02' B4C, I thought think it has a PS cooler? I have that oily gooey ****. I'm gonna try to flush it after a pressure test. F__ck__g engineers; more parts = more problems, more inter-connected parts = more F__ck__g problems!
Your problem is that you waited too long to change your coolant.
Run a good flushing agent through it. Flush with fresh water. Refill with 50/50 mix of Dexcool and distilled water.
There are lots of arguments about what's better, DEX or green, but the important thing it NOT TO MIX THEM. Nothing wrong with Dex, just don't wait so long to change it. As you now know, it turns into slime.
Run a good flushing agent through it. Flush with fresh water. Refill with 50/50 mix of Dexcool and distilled water.
There are lots of arguments about what's better, DEX or green, but the important thing it NOT TO MIX THEM. Nothing wrong with Dex, just don't wait so long to change it. As you now know, it turns into slime.
You should see the inside of my radiator, looks horrible with all that brown gunk in it. Engine runs plenty cool though and it isn't in the waterpump so I haven't done anything with it.
Once again I don't get the folks that support Death Cool. They say that as long as you change it regularly then it won't sludge up or cause problems. Isn't the whole point of Death Cool supposed to be a coolant that lasts 100K miles without touching it? What's the point of using Death Cool if you have to change it out as often as the green stuff?
TECH Resident
Joined: Jul 2007
Posts: 749
Likes: 1
From: Spokane, WA
I had the dex-cool gunk. After my coolant flush when I installed a new radiator NEVER will I put that **** in any car EVER. It was truly amazing how much sludge was in the coolant. it was almost like used oil but not quite so thick. Then even more came out running some Super Flush through the system to make sure the heater core and everything was all cleaned out. I used Prestone Extended life coolant instead. No sludge issues that i know of and you still get the extended life.