ok i bought a new thermostat and put it in and now thermostat wont open and all the coolant stops when it reaches thermostat and leaks out of the radiator hose. What is the problem here.

Oh by the way it leaks through the clamp on the radiator hose so there is a lot of pressure but the thermostat still wont open.

are you sure you put it in right?

just go through the steps again and make sure its in the correct way. It might be a faulty thermostat.. but it can't be cuz its brand new.

good luck:thumbsup

also... make sure u didnt put it on backwards.... when they break, they are suppossed to break in the open position... my brother put the one on backwards on his civic... im not sure if u can even put it on backwards on a 420A but its worth a shot.

i might put it in backwards i dont know ill check again tommorow but is it possible in 420A to put it in backwards

Your clamp isn't tight enough. Stock spring clamps just plain suck. Put a real clamp on it..