"Paper" failed then likely Tstat is not flat or dirty etc or used wrong gasket.
Many "paper" and cork gasket use High Tack but Many Tstat housing have problem from over torquing the bolts etc.
RTV takes 24hr or more to full cure. Cold weather can take days to cure. Freezing weather might many can't cure or takes week or more to cure. Dry and not sticky IS NOT full cure. You can't load coolant or drive until then.
RTV hate oil/grease, coolant, rust, or dirt on pieces to seal. Best last step is brake cleaner.
Above work on v6...
L4 have two types. If L4 Tstat housing have thick flat flange then won't work and you can't get new silicon "o-ring." I made one from flat cork supply, apply w/ little RTV and then let RTV to cure for 2-3 days.
Dr. Ian Malcolm: Yeah, but your scientists were so preoccupied with whether or not they could, they didn't stop to think if they should.
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