gearheadboy
15 Year Member
Ok dude. From here I think its just junk in the block. Whether it be rust or old coolant rust combo. Either way I don't think its oil. Most times if it is oil or auto trans fluid it makes the hoses all greasy on the outside. I think the coolant is breaking the crap loose in the coolant passages of the block. You will NEVER get it all or even most with water. Run some cooling system flush from the auto parts with some coolant/water mix. Run it for more than a few minutes. A few days. Open the drain and put your garden hose in the radiator fill hole. Run clean water in while the engine is running and let the drain open while you do it. SO engine running, cap off water going in, drain open. Do this for a bit. Shut it down, drain it and fill it with flush and coolant/water mix again. Run a few more days. Flush it again with water and add coolant/water mix without flush kit. Drive it and forget about it. It will almost never be pretty again but it wont be sludge.