Hey, just bought a new to me 2001 isuzu trooper. Previous owner bought it at auction. Said it was driving fine, but when his friends drive it one day it was overheating and he hasn't driven it since. I get in there to replace the thermostat (fan clutch and radiator have recently been replaced) and I cannot get the dang intake manifold free from the engine. I pulled the 4 nuts and the nut from the egr valve pipe, but it's not budging. I'm concerning the last person who replaced the manifold gasket used some sort of adhesive. Thoughts/advice???

 

Well, first of all, how did you gather that you need to change the thermostat?