Hi all,

I own a 99 Blazer 4WD LS.

I am a bit puzzled about this one; I keep finding a black rubber like particles floating around the radiator near the radiator cap! and I keep losing water from the radiator and the reservoir every 2 weeks or so with 3 hrs driving a day.

Anyone has an Idea where that substance could be coming from.

here are the facts about the car.

just hit 200K (although the problem been there for a long time since 150K or so)
Replaced the Radiator, heater core, hoses, radiator cap, flush the system.

I will be replacing the intake gasket as it just started to noticeably leaking.

this problem does not seam to effect the engine performance and the transmission (Rebuilt with extra cooler) always jerks on first and second when its (500 F) outside in summer here in Arizona.

I appreciate any hints on what this substance might be as I will correct for it with new parts as I tear down the upper end of the engine soon.

Thanks

 

Could be pieces of the intake gasket, but I don't know how likely that would be. I guess if you're losing that much water it may be more likely than not.

There's no water in the oil/elsewhere?

 

that is a possibility, the only problem is that I periodically remove some of it over the past 3 years. before and after the maintenance mentioned earlier.

 

Could the black stuff be a stop leak that was added in the past? I have used Barrs leak before and it is black or dark brown in color. Some of it will usually end up in the over flow tank and leave a ring inside.

Blazeme

 

I know for a fact that the previous Owner have used the nasty stop leak stuff. Its brownish in color because it has fine particle copper in it. I have flushed the radiator many times and actually replaced all the cooling system components. I know how that stop leak stuff looks like and its not it. the stuff I am talking about looks like tire shaving. as if the hoses are being scraped from the inside or some rubber thing is being constantly chewed on in the cooling system. the weird thing is that I have all new hoses and still see that stuff.
I am not sure a gasket would generate that much Rubber, It would have leaked long time ago in my case.