COOLANT LEAK

Just noticed I have a coolant leak coming from the drivers side of the radiator.  Its leaking coolant at the hard line just below the upper rad. hose.  It looks to be coming from between the plastic of the radiator tank and the metal hex shaped fitting the hard line threads into.

The hard line on the drivers side must be the oil cooler line. (LT1 car) In the manual, the hard line sits above the radiator hose. (so, i'm a bit confused here) Sounds to me as a crack in the radiator side. Does the leak gets any worse with the engine running (i.e. when the system is under pressure?) If it is really a crack in the side, there must be a spray of coolant coming out when the system builds up pressure. Is your engine coolant reservoir still at the right level?

Here is a pic of the area I am talking about. Can this be fixed or does the radiator need to be replaced because its plastic? [You must be registered and logged in to see this link.]

tighten the nut up a little,. don't crack the res,.

+1
try that first

Yup, had the same issue on my C10. Leaking from the oil cooler nut, tightened it up and it has subsided.

Always check your nuts first.

Heh.

Put about half a turn on the nut and after further inspection there is a very small crack/hole in the tank. Woohoo!!

small crack holes are fun to fill,...er..

jb weld is your friend,.

drain the rad clean the crack with brake kleen,.
gob it up,.

Nick

When I fixed the various problems with my cooling system and got it to pressurize properly, I got a leak in that same exact spot. The plastic tank was very obviously split right at that point, and there were signs of other cracks forming, so I got a new radiator. Also in my case, since the cooling system was so badly neglected, I wasn't very confident that anything in the system was any good.