I have a California Air Tools 4610AC that needs the pressure relief valve replaced.  The valve is brass and is installed into one of the pressure switch ports with some sort of HARD sealant (like red loctite).  It is NOT the normal soft sealant one would expect to be used--it's like CAT doesn't want you to remove it, period.  The brass relief valve broke when I tried to remove it.  Red loctite usually breaks down at 350F but I don't think the pressure switch diaphragm is going to stand that kind of heat.  Does anyone have any suggestions besides drilling it out?  I'm afraid I'll destroy the pressure switch if I try to drill it.
Best regards
JL4C