For a few weeks now I've noticed a slow leak from my radiator. When I park the car it will leak a small puddle, about the size of my hand and then stop after about 15 min's or so. I've been searching high and lo for the actual source and the closest I can come to one is the place where the top part of the radiator (containing the filler cap) joins the main body of the radiator (containing the fins). There is a small amount of coolant seeping out all the way around in this location. Strange thing is the intermittant nature of this leak. It hasn't done it the last several times I've driven the car. Is it likely that a leak can repair itself? Doesn't seem so to me. Anyway. When checking my oil today I noticed a splattering of greenish white deposit all over the fron of the engine. Most noticable on the front of the valve cover, the upper radiator hose, the front of the air cleaner housing and the front of the thermostat. And it's on the inside o the cooling fan blades as well. I have to assume this is from the slow leak and that the fan is blowing this stuff all over the place as it's turning. These pictures should give a clearer picture of what I mean. Am I right in my diagnosis or there something else going on?

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2021 Chevrolet Spark
Formerly...
2000 GMC Sonoma
1981 240D 4spd stick. 347000 miles. Deceased Feb 14 2021
2002 Kia Rio. Worst crap on four wheels
1981 240D 4spd stick. 389000 miles.
1984 123 200
1979 116 280S
1972 Cadillac Sedan DeVille
1971 108 280S