Water outlet gasket issues.

[kamikaZeS30]

So, as my car comes further along I get to smaller and smaller items. I have not had any issues with over-heating or the engine running on the warm side (even in Southern California traffic), but I do have a coolant leak. It doesn't appear to leak while the engine is running, rather it happens almost exactly 24 hours after it has been run and the engine is stone cold. I know where the leak is, it's in the water-outlet/thermostat housing on the intake manifold.

 

Last night, I went and picked up one of the Fel-Pro performance rubber-silicone gaskets with the steel inserts. This probably would've worked wonders, but apparently it's not made for my water neck thing, the one I have is the supposedly "new-style" O-ring. So, this disappointed me and I just slapped some RTV on the O-ring to help it seal, then put everything back together (with lock washers this time, sorry, long story...). Drove it from where I did the work to back home, engine was able to reach operational temperature and remain there for a few minutes.

 

Went to check on it today and, lo and behold, it's still leaking out of that damned O-ring. I *think* my intake manifold side is good (it could be uneven, this wasn't a very expensive aluminum manifold, probably Chinese made), I cleaned it before I put everything back together.

 

I am looking for advice from folks that have more experience with the SBC than I, would it be alright if I took it apart again and just slathered a nice thick ring of RTV on it and squished it down to torque and then waiting a few hours before putting more coolant in? Is there someplace that still sells the flat-gasket type water neck housings? I used these Fel-Pro gaskets on all my external oil seals and they seem to be completely dry and leak-free.

 

It's bothering me because I hate that burning coolant smell when I'm driving.