I just replaced the donut gasket in the input side of the catalytic converter along with new bolts/springs. there is a leak with the new gasket..The bolt and spring dont seem to pinch the flange together tight enough to seal the joint. did i need to add sealant when i put the new one on? which sealant? were the autozone bolt and spring combo the wrong way to go?

 

you do not need any sealant forsure but i dont really see how you could get the wrong bolts as long as they are long enough i dont even use the springs that your talking about and it still seals it off

 

Too long is the problem. click the link to see what i purchased. image

the bushing part of the bolt comes in contact with the flange on the A pipe before the spring really compresses completely against the flange on the cat and the head of the bolt. see picture. my 1st grade art teacher would be proud!

I'm going to try and return it if they will take it back once it has been installed.... either way i need a new set of bolts. Will sealant help at all? is it something that is recommended for exhaust gaskets?

 

Sealant is not necessary if it's put together with the right parts. It is built that way so that it can move slightly when the engine shakes. If you used some sort of cement to seal it, it the cement would just crack when it moves.