ok, so when i bought my truck ('92 s10 blazer 4.3L Z) it had no thermostat, I promptly put a new one in with a new gasket and rtv, it sealed for maybe 2 days and started leaking again. I replaced the housing and gasket again (both times gaskets were fel-pro) and used rtv again, it sealed for a couple weeks, now it's leaking yet again, last time it was at the back of the housing, now its at the front..seems like it leaks from between the gasket and the housing as coolant is beading up there.

 

maybe let it set up over night or as long as you can. i usually do that when replacing intakes instead of just starting it up let it sit for 12+ hours

 

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