: Brown sludge?



BLMDeville
05-24-12, 08:12 PM
While replacing my water pump i noticed some brown sludge line my radiator over flow tank.

Any one know what it is and what might cause it?

dennis93coupe
05-25-12, 01:03 AM
It might be the stop leak dumped in it over the years. I have heard GM does not recommend using it anymore, although they still sell it. Make sure the small hose from the radiator to the reservoir isn't plugged. I take mine off and flush it out best I can if I change the coolant. I'm getting ready to change it out and am going to order a new reservoir this time.

Sevillian273
05-25-12, 09:04 PM
I read about this a while back, I forget what it is... I've seen this a number of times even in vehicles that dont take the powder. I believe it has something to do with the coolant vapors condensing inside the tank and forming that brown almost 'foamy' stuff kind of like standing water does in a mud puddle. I dont think you need to worry about it. I usually take the tank out and flush it. I see it more often on vehicles with pressurized tank systems unlike your 4.9's 'overflow' type.

Ranger
05-25-12, 10:16 PM
Yeah, It's most likely sealant tab residue.

dennis93coupe
05-26-12, 10:07 AM
I'm with Ranger on this. Just now getting close to having most of it flushed from system. I don't think you will ever get rid of it completely, even with a heater core flush.

83CADMAN
06-02-12, 06:18 PM
Just because Caddy does not use it any more doesnít mean the old cars donít require it. I allways replace the seal tablets in my 83, HT4100.

BLMDeville
06-04-12, 12:08 PM
Where are the seal tablets?

dennis93coupe
06-04-12, 10:26 PM
You can get them from the stealership. The GM part number is 12378254.

Ranger
06-06-12, 11:18 PM
Where are the seal tablets?

Where or what? They are Barsleaks tabs (product code HDC). The powdered version is (G12BP). Get them at Walmart, dealer, most parts stores. As for what they are, see the sticky in the Northstar forum.

dennis93coupe
06-07-12, 01:47 PM
Here's part of the old package I use for a book marker...

http://i1069.photobucket.com/albums/u461/dennis93coupe/Engine/12378254CoolantTabs.jpg

http://i1069.photobucket.com/albums/u461/dennis93coupe/Engine/12378254-2CoolantTabs.jpg

dennis93coupe
06-07-12, 01:53 PM
Here's part of the old package I use for a book marker...

http://i1069.photobucket.com/albums/u461/dennis93coupe/Engine/12378254CoolantTabs-1.jpg

cadchris
06-08-12, 01:35 AM
Maybe save it and mix it with "Pink Slime" to make a better burger........yeah.......I know.......:cookoo: