Sludge in the Coolant reservoir

[red94fiveo]

I was emptying my coolant reservior (its out of the car) to paint it today and I probably dumped out an inch or two of sludge from the bottom that has the consistency of mud. Is this normal? What could this be from, just normal deposits or something I need to look into. BTW- This is on my 82K stock block.

 

[94GTLaserRC]

When Vib and I took mine out 15 mos ago (about 75K miles) There was a ton of gunk in there too. Used some simple green, and shook the crap out of it to loosen the stuff.

RC