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Finally getting around to repalcing the catalytic convertor on ym 2004 Cooper
Unfortunately I ran into a small issue.
Getting the bolts off the exhaust manifold was easy but when I got the car up on jacks fully expecting to just cut the bolts off at the coupling after the convertor, but "There was no coupling". I had an emergency work done a few years ago when I was traveling. They actually cut the pipe right between the O2 sensor an the coupling and welded a new pipe all of the way to the muffler. I had completely forgot about that repair.
I think I have a few options
cut the pipe off between the weld and the O2 sensor and take the pipe and muffler to a shop to weld a coupling plate in place.
Get a coupling plate welded to a short piece of pipe that would attach the the new catalytic convertor . The I could cut the existing pipe to correct length and use a union to join the pieces together.
Get a new catback system.
Something else?
The muffler seems to be ok and the pipe virtually looks new.
What would be the best path forward? Appreciate any thoughts and comments.
Also, if you’re replacing the manifold with a used stock unit I would take it to the welder and have them reinforce the pre-cat which should help to prevent it from failing in the future. Here are a couple of threads about it:
Thanks fr the comments guys. That was where I was thinking of going so good to have the confirmation.
I now have the cat out. Spent more time cutting through the pipe than getting it out of the car. Cut right by where the O2 sensor was located. The new cat is several inch longer so the exhaust shop will have plenty of Pipe to work with. Now I have to get my exhaust and muffler off of the car so I can take it to the shop. Stupid question;I am assuming they will know where to cut the pipe and weld on the new flange?
If replacing it with another stock manifold take both there and a good shop should be able to compare them and figure out where to cut the pipe and the orientation of the new flange if it can’t be rotated after welding.
Thinking more about this, option 1 is probably the cheapest, but you have to transport a big heavy exhaust system back and forth and hope everything lines up after.
Option 3 should be simpler if you can have the exhaust delivered to you, but can be expensive to get a quality exhaust without installation/fitment issues out of the box.
What condition is your current exhaust in and did you ever plan on upgrading your exhaust? If so, and having the car down while waiting for the new exhaust isn’t an issue, now might be a good time to do it and not have to go through the extra labor in the future.
I would like to thank everyone for the helpful comments. New cat is in. Followed gumbedamit recommendations to replace oil housing and oil cooler gaskets when I was in there. With the catalytic convertor out, that was a piece of cake. Muffler ship created a flange with a slip/compression joint so all I needed to do was cut the exhaust pipe back to the muffler to the correct length.
Given that the Cooper has 125k, I am sure there are some more items for me to deal with but for now, I am good. as I will be able to pass my emissions test in July.
PS Looking at the old cat, it isn't surprising that I was getting a P0420 code as there was no catalyst in the calatytic convertor. Some how it must have been jarred lose and bounced around until it turned to dust and went out the exhaust.
I have a clogged converter in my 2005 mini cooper r50 and I'm trying to figure out my options for replacing it. Is it possible to extract the converter-manifold unit without removing engine mounts and other parts around the engine/transmission area?
