What is the best way to loosen frozen thermostat housing bolts?

 

PBlaster then make sure you have right size torx bit. Once you mess up the heads they will be a bitch to get out. Once I got mine out I replaced them with hex bolts.

 

+1 to replacing them with hex bolts!

 

thanks for the help.

 

Yes do replace them with hex head bolts.

It makes life so much easier for the next time you need to remove the goose neck/thermostat.

Luckily for me the previous owner did just that!

 

Or go to the dealer and by the screws the new ones are supposed to be stainless steel.

 

Well, if they are not damaged yet and are still tight in there. I suggest tapping them with the right torx bit inside with hammer on top before trying to open them. I guess this helps them to break the bond and makes it easier to loosen them.

 

Thanks to everyone for the advice. I did manage to get everything out, got a new housing (the old one was cracked) and got everything together.