Does it have to be coolant-specific rtv or will hitemp red work?

 

Red should work, but some thing specific for coolant will work better.

 

Well, I got everything back together and now I have a new coolant leak 😭. Coolant is leaking from the front-left area of the engine, near the thermostat housing. When I installed the lower intake manifold, I put water pump rtv on both sides of the gasket, around the coolant passages to avoid a leak. I replaced the thermostat gasket, still leaking. I suspect the lower intake gasket is leaking already. I haven't even got to start it yet☹️. Should I just install the new gaskets dry with no sealer? I also didn't use the rubber end gaskets, just a thick bead of black RTV. Anyone have an experience like this? Any help appreciated.

 

Make sure you verify 100% that it is the manifold that's leaking. It is very easy for the thermostat to drop out of place during install, and prevent a seal. You can rent a cooling system pressure tester from a local part store. check for signs of coolant in the oil and in the cylinders.

 

I would be a little more careful and use a sharp scraper or razor blade/scraper and 180-240 sandpaper by hand. Do all the cleanup first before lapping, seals, paint, etc.
Be sure everthing is spotless before final assembly.