Changed my water pump so I thought id change my thermostat as well. When I took it out I realized the auto part store gave me the wrong thermostat. I put everything back together and while filling up my radiator with coolant the thermostat housing started leaking. Do you have to rtv a seal between the housung and the top that connects to tye upper rsdiator hose? Thanks for the help in advance

 

Prolly too late at this point... you MUST order the tstat from the dealer as NAPA/OReilly's claim they have the right part but it is in fact incorrect. Do it right the first time and order the part through the dealer or from mitsubishiparts.net.