Replacing header pipe and cat.I see the 3 nuts holding header to manifold.They are rusty and will have to be cut off.I dont see the other end of the bolts coming out the other side of the manifold.They appear to be recessed in the manifold.Can they be replaced? Thank You

I replaced my very old and over welded downpipe with an aftermarket DIRECT REPLACEMENT one from a company called "WALKER MUFFLERS"

Now it is for an 1986-88 volvo B230f but fit like a glove on my 1990 245 B230f and the best part was that it is $149.00 CDN compared to the dealers $444.00 CDN so new beats rusty for cheap money

Capt'N Crunch.

Hey Cap'n'
Did your walker have the spin flange on the cat end. My downpipe is pretty well shot, too.

Marten

No; the CAT and the pipe were straight inline connections. Remember this is a aftermarket pipe and somethings you have to be flexable about. What I did to install the O/S is to use a 2 1/2 inch pipe flared as to go over the inlet of the CAT now I can adjust the angle of fit and second I gave myself a stronger wall thickness to which I can install the O/S .

Capt'n Crunch

They are studs similar to those in the head to handle the exhaust manifold.

Due to age and such they can be tricky. Use lots of penetrating oil and heat and remove in a alternate pattern (5 or so turns each bolt in series so as to not load one stud with all the remaining torque). That way they don't snap.

Drilling out and rethreading and reinstalling the studs involved removing the manifold, which can lead to head studs breaking and that means removing the head...

I believe that what you are referring to is the "down pipe" that runs from the exhaust manifold and then on back. These nuts can be tough to get off of there but I have never run into one I couldn't break loose with an impact gun and penetrating oil. Now, if you absolutely have to cut the studs off that are threaded into the exhaust manifold, leave the studs as long as possible as you will have to be able to grab ahold of them to twist them out. They can be replaced but it is a royal pain in the (edit), so try getting those nuts loose first!

jorrell