Black Sludge in Radiator?

[c2computer]

Hey guys,

Bronco has been running hot lately, so I checked it out this morning and found black sludge in the radiator. It looks like it is only in the radiator, and only on the top half or less of it. It is stuck to the walls of it (maybe why running hot?) and no where else. Not in the hoses, thermostsat housing, manifold, etc.

I am not sure if it is oil, no loss in power, seems to run fine otherwise, the engine only has about 2000 miles on it. I drained the coolant, no oil anywhere, looks very clean and clear, no evidence of oil.

It is an all aluminum Be Cool radiator so I thought maybe something is reacting with the aluminum? Any help is much appreciated. Thanks

 

[c2computer]

After doing some research, it looks like the problem lies with the Dexcool. There are numerous class action lawsuits against GM right now for the coolant related problems and for putting it in their cars since 1996.

I was amazed at how many people are having the same issues and symptons as me when I checked around. Looks like I will be flushing the system and putting the green stuff back in. Any ideas on how to clean the radiator would be great. Thanks

 

[Jeepster]

Some of the cleaners on the market are a. not worth the money, or b. not good for Alum. I have heard of a product recommended by Mercedes and is based on citric acid. Citric acid is an excellent cleaner that will not attack aluminum. Sorry I cant recall the name right now :

 

[c2computer]

Thanks, I think I may look for an engine sludge remover that is safe on aluminum blocks. What a pain in the a$$.