I installed a 192 degree thermostat and i used some gasket gunk and it leaked.I am retrying to seal it again but with no gunk on the gasket. Am i doing the right thing? Any one who has installed a thermostat on these windstars know what a job this is.Thanks for any help on this.

 

Define gunk..

Generally with any thermostat weather its sealed by an oring type seal or paper type one of the first things you check is that the outlet housing face is flat, not bowed at the ears, no excessive pitting or corrosion on the mating surfaces. Gasket materials (if bought a a box store) type can be a problem if its not a more dense paper like OE or too thick causing the housing to bow when tightened. Universal type gaskets with over sized or elongated holes are no good.. Oring type thermostat seals should always be replaced..

If its all good, usually a lite coat of a sealer that 'sets' is best. Tacky sealers, aviation, slippery silicons etc.can tend to squeeze or stress the seal material. When using a setting type sealer, or any for that fact, make sure some dry time is met for the best results before pressurizing the system..