agreed
I replaced my engine back flushed the rad, back flushed the heatercore removed and cleander the over flow and I still get some signs of that old Dex cool in my system.

 

Ok, update time....

I did the pressure test on the cooling system. Pumped it up to 15.5 psi and then let it sit for 15 minutes to see how much it leaked down. In that amount of time, the total pressure loss amounted to 1 psi on the gauge. I was told that this was acceptable.

However...

The source of that 1 psi loss showed me where the coolant on top of my intake is coming from. It's welling up, or seeping from, around one of the intake bolts. I could actually see the coolant seep from the bolt and trickle to where the rest of it had pooled up. Am I correct in assuming that whether or not any coolant is yet mixing with oil, the leaky bolt means that the gasket is failing?

How rough is a LIM job? With the engine in the car, that is. Is it something that someone with no past experience in pulling the intake can do, or should I just have an experienced professional do it? I was told that a stop leak product might fix it, but I don't want to plug the leak to the outside if something much uglier is inevitably brewing underneath...if you know what I mean...

 

it may be the coolant is leaking by the bolt. could try pulling that bolt and put some rvt or thread sealant on it and put it back on. would be best to change the gasket to be on the safe side. i would recommend you pick up a factory service manual for your year camaro.

 

Who told you that was acceptable? 15 minutes with no drop in pressure is what I use. When looking for small leaks I have put the system under pressure for up to 4 hours. It should not drop pressure in the 4 hours if everything is working right.

Like I said before the intake is a common issue with these. Dont mess around to much because if it starts leaking to the bottom it will wipe the motor. The opinion on how tuff it is will depend on your skill and tools. Its a lot more involved then an intake on a 73 and the cowl make it a little tuffer then say a 91 TPI but I think it is easier then a LT1.

 

Thats probably exactly what it is. I used to see that 3-4 times a week at work so dont feel bad, it happens alot. I would take it to your nearest "Full Service" not Jiffy Lube or places like that and have them flush it out with the machine. The machine forces the fluid around at about 40 psi so it should break up the chuncky crap that the ethylene glycol and dex-cool make when mixed. I suggest telling them that you want about 20 qts of water flushed through to make sure that all the gunk is out of there, last thing you want is for to clog up your thermostat. Then spend the extra few bucks on G-05 coolant (looks gold). I havent had any problems with it and its 100% synthetic and last twice as long.

Hope this helped

 

A guy I work with who worked for years as a GM mechanic. He said that the leakage though the bolt seems to account for that amount of loss.

I also tested the radiator cap and found out that the thing is completely shot. It holds absolutely no pressure with that pressure tool.

I'm going to flush out the coolant tonight and change the oil while I'm at it. I think I may also try the RTV-on-bolt idea and watch it closely over the next few days afterward. Even if that works, though, I'm going to treat the repair as a band-aid and start making preparations for getting the intake gaskets done. I know that these GM V6's are notorious for blowing intake gaskets, and have been waiting for the first sign of trouble for a while. In the meantime, I'm putting conventional oil in it so that any signs of coolant in the crankcase will be blatantly obvious.

UPDATE: Changed the oil. While the oil was dirty, it didn't seem to have any coolant in it. No discoloration, froth, or antifreeze smells in it. Just typical, high mileage engine-used oil that was 400 miles away from its regularly scheduled oil change.