https://www.brickboard.com/RWD/volvo/1644176/220/240/260/280/diy_volvo_240_exhaust_replacement.html

i wrote a few days ago

exhaust replacement is pretty straight forward with one exception. the connection between the cat and the header pipe is poorly designed and increasingly so once volvo went to the spin flange and donut in the early 90's.

i have taken to resorting to this bit of surgery on all 240 exhaust systems i repair/install and have had zero problems as a result with 100% sealing rate success.

this method is simpler, cheaper, easier to install and effortless to take apart if components needs to be replaced separately.

1. use a reciprocating saw and cut the header pipe end which meets the cat flush so you have clean end. remove as little metal as possible to achieve this

2. do the same on the cat end.

ps: this clamp type is ideal for all joints that leak if you want to cut away the offending leaking pipe joint

3. you now have two pipe ends with no flares or bumps and no flanges. a small gap exists between these 2 pipes.

4. purchase this clamp and install. end of story. no leaks, no rust on the clamp and effortless removal should you need.

http://shop.advanceautoparts.com/p/nickson-2.00-band-clamp-e20st/10078731-P?navigationPath=L1*14932%7CL2*14983%7CL3*15314

a stainless steel 2" band clamp