After several bottles of catalitic cleaners attempting to clean my cats with accompanying CEL and verified codes, without success, I'm considering removing the existing ones for cleaning or repair. Can anyone advise of their experience on removing the cats for cleaning/ refurbished, how difficult to disassemble from the exhaust.

 

They come off quite easily IF you have a lift. On stands it's quite a bit more difficult.
You don't say which year vehicle you have, and that does make a bit of a difference.
Do you have the dreaded P0420 code? "Cat Under performing"? Or, do you have other problems which affect performance and drivability?
Your cat MAY have just worn out, like mine did. On my 2010 XKR, I removed the left cat in about twenty minutes, but I have a lift. I followed a bunch of advice from the Interwebz about how to manually clean it, so I did three different procedures. Everything flowed very well THROUGH the media, so there weren't any actual clogs. I reinstalled and STILL got the 0420 withing two days.
SO, I bought one of those Sensor Spacers for a couple bucks and installed it. That took a bit of work though, as the sensor hit the transmission before it would thread into the cat. I shortened each end of the spacer a bit and finally got it in. NEXT time I would install the sensor/spacer BEFORE I reinstalled the cat.
Anyway, that was a few months ago and the code has never reappeared.

 

What does the sensor spacer actually do Cee Jay?

 

As I understand...The 02 sensor spacer (bung) elevates the sensor somewhat out of the cat outflow to trick the system into reading less polluted exhaust..thus better emission test pass chances. It should be considered a temporary fix only . The root cause of the 420 code should still be investigated...ex. fuel trim or damaged/clogged cat.

 

 

My cat took a **** because I had a stuck open injector on that side. Being drenched in raw fuel while still trying to run did it zero favors. Which is why I flooded the cat with stuff to ensure it wasn't clogged at all. I also borescoped it. Nice and pretty the whole way.

 

If a cat is cleaned throughly and results show good flow, maybe its the catalyst materials themselves have been totally converted and should be replenished, rebuilding is avail from several online
options. I've heard/read that new sensors should be installed with new cats. I'll ask my rebuiler if I end up going that route.