I would never use any kind of RTV on any head gasket; IF I used ANYTHING, it would be either the Copper Coat spray/ or if not that maybe the Permatex "Hi Tack" spray. but for a head gasket for a small engine I can't say that I remember "ever" using anything on a head gasket at all in 35 years of playing with them (since I was 12)
I have never been an RTV fan for anything, though some use it (by itself) for anything from valve covers to oil pans and water pumps, the only thing I can ever get to seal with that crap is rear end covers.
the only other place I'll use RTV is doing an intake manifold on a V8, in the 4 corners where the end and side gaskets meet.
I have seen people though that think they need a whole tube on a thermostat housing, and wonder why that new thermostat "don't work" after they plug them up with the crap.
Edited by dodge trucker, February 15, 2015 - 11:56 PM.