Black Fluid in Radiator
Junior User
Joined: Jun 2000
Posts: 73
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Black Fluid in Radiator
i put in a new 302 in my '78 F-100. i kept a few of the parts original parts on the truck, like the intake manifold. the manifold was pretty rust so i flushed it with some chemicals to get it out. once i put it one a put the fluids in a ran the engine the coolant was a little hazy and had a white tinge to it. so i flushed the system a couple of times and added more coolant. i checked again after a few mile and it was still a light green color. so i flushed it again. after 100 miles i looked again and now it looked like there was a black film on floating on top so i drained the system again. the lite green coolant can out again and then when it was almost empty the black stuff came out. the black film didn't seen like motor oil because it was fused with the coolant and wasn't seperated like oil would be in water. anyways, i added more coolant and ran it some more and the black stuff was back on top. any suggestions to what this stuff is and a sure fire way to totally flush your system and get rid of it? i always used radiator flush when flushing and always followed directions. thanks for your time.
Senior User
Joined: Apr 2001
Posts: 128
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Black Fluid in Radiator
Does this pickup have an automatic transmission? If so, I'd say you've got a leak in your transmission cooler, which is an integral part of your radiator from the factory. Engine coolant cools the transmission fluid, so if you have a leak in that cooler, it could seep into your coolant. Might check your transmission fluid to see if it is low or funny looking/smelling.
Senior User
Joined: Jun 2001
Posts: 293
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Black Fluid in Radiator
Sounds like someone put Bars-stopleak in it.Or maybe some other brand. Just a guess.
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Garett
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"There's a little red button there,kid...don't ever, ever touch the red button!"
Garett
Lead Driver
Joined: Nov 2000
Posts: 6,628
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From: Albuquerque
Black Fluid in Radiator
Maybe you got a little carried away with the silicone sealant? The antifreeze might be dissolving the extra.
1977 Ford F-100
400m/c6/4:11/Gear Vender O.D.
Crane hydralic roller, forged, ported polished,Deamon,Edlebrock, yada, yada, yada
280,000 miles
Stock on the outside
modified/rebuilt everything
1977 Ford F-100
400m/c6/4:11/Gear Vender O.D.
Crane hydralic roller, forged, ported polished,Deamon,Edlebrock, yada, yada, yada
280,000 miles
Stock on the outside
modified/rebuilt everything
Posting Guru
Joined: Jul 2001
Posts: 1,613
Likes: 2
From: Gainesville, FL
Black Fluid in Radiator
Your description is peculiar to say the least. How much black fluid is there and how many miles do you have to drive before you see it? The antifreeze is an anti-corrosion inhibtor. When iron oxide "rust" is chemically neutralized it becomes iron ferrite, which is black. If you filtered your antifreeze through a T-shirt would you see any solid perciptant "scag". It is possible to suspend iron in a liquid state through the use of sodium hydroxide, an acid, I think. If the coolant flush you used has this chemical in it, it is possilble that iron ferrite, in solution, is what your seeing. The question is, at this point, Why doesn't this black liquid go away after repeated flushings. A possible answer is that there is a residual amount caught in your heater core. If that's the case you may notice your heater core leaking soon, ouch! Give me some more info, I've seen it all.
Kingfisher
Kingfisher
