Catalytic converter cleaning...would you do it?

[BamZipPow]

A new OEM converter fer my T-100 lists around $1600 from the dealership. Online discounts drop it to about $800 not including shipping.

This is the technical paper I am basing my converter washing on...
http://www2.ucy.ac.cy/~chpgsc/arthra...%29%202030.pdf

On the other hand, there are a lot of cars with cats in California, big market, money to be made if your idea works.

Exactly...

After 30 minutes...


Residue at the bottom of the CatWasher...

[metromizer]

That paper has been reviewed, then published, looks like a decently thorough investigation of one failure mode of one Mazda catalytic converter.

Do you have any idea why the researchers never did anything with the idea?

I would interview a couple of muffler shop installers to see how many cats they've remove that are candidates for cleaning/rejuvenation treatment. You know, look physically good (the ceramic isn't broken, case not rusted through) but aren't working as advertised.

Another thing to consider with such a cleaning system in a commercial application is the waste stream... concentrated heavy metals, oil, etc in high Ph water solution might be difficult/expensive to dispose of in California. There has to be a way to post-treat on site, but it might be expensive.

[BamZipPow]

Originally Posted by metromizer

That paper has been reviewed, then published, looks like a decently thorough investigation of one failure mode of one Mazda catalytic converter.

Do you have any idea why the researchers never did anything with the idea?

I would interview a couple of muffler shop installers to see how many cats they've remove that are candidates for cleaning/rejuvenation treatment. You know, look physically good (the ceramic isn't broken, case not rusted through) but aren't working as advertised.

Another thing to consider with such a cleaning system in a commercial application is the waste stream... concentrated heavy metals, oil, etc in high Ph water solution might be difficult/expensive to dispose of in California. There has to be a way to post-treat on site, but it might be expensive.

Not sure why it wasn't put into play...or anyone else picked up the ball. Doesn't matter to me...I'm having fun!

Baking soda will easily neutralize the weak acids in the residue solution.

There isn't an incentive from the shops' point of view as they will lose money fer cleaning yer converter vs replacing it. They do make some money on the parts (parts markup %) as well as the labor fer removing the old and installing the new. They also make some money fer recycling the old part. No shop would throw money out the window fer a cleaning process compared to what they earn fer remove/replace. If they did, they be a fool.

This process is more fer the DIY'er who might have an option to save money compared to a costly replacement. With the exception of the cost of the wiring (switches, box, cord and plug) and the chemicals, everything else I've put into this CatWasher were scrap materials.

[BamZipPow]

After 2 hours of cleaning and backflushed with tap water...

[BamZipPow]

Just got done with the 2nd wash and backflush. I ended up heating the solution on my induction burner fer the entire solution...talk about hot!

Here's the final result after two 2-hour washes with a citric and oxalic acid solution. A simple rinse from front and from the back. Used my shop vac in blower mode to blow out as much water as I could...





Used 2 new OEM gaskets along with some anti-seize. Shouldn't have to worry about someone taking off with my converter as I also have a full belly pan and side skirts fer them to contend with as well.

If I were to redo this...I think I would try a hot sprayer method instead of the full flow method. At least on the 2nd wash it could be more efficient as I could point the sprayer at the spot(s) I wanted to dissolve away. Of course...with the full flow method I could've washed the converter fer hours on end instead. I just needed a better way of keeping the solution at temp. I did rotate the converter at 90° every 30 minutes so I could git enough coverage.

I did notice after I started up the engine I was gitting water vapor from the exhaust pipe...like when the weather is cold outside in the morning...except it's 82°F and super humid from all the rain. I wonder if that's a testament to the effectiveness of the converter.

[oil pan 4]

I always used a 5/8'' concrete drill bit mounted in a hammer drill....

[BamZipPow]

So as I understand it so far...no one here would clean their converter. Smash it out fer better HP and MPG...don't bother with the emissions. Aftermarket cats only cost $100.

Guess that I've gotten my converter cleaned I can scrap my washer now. Thanks fer the inputs.

[CigaR007]

I would clean my car's catalytic converter but given the complexity in removing it, I much rather not touch it since it seems to be working as it should. That alone tells me the catalytic converter is running at near 100 % efficiency, even after 11 years.

I do appreciate the effort you put into this though. Any action that can prolong the life of a vehicle and its parts is commendable.

[ConnClark]

I would worry what chlorine in the water would do tho the catalyst.

[Mustang Dave]

Originally Posted by Milwaukee

I am not sure but doesn't water kill cat convertor?

Every gallon of gasoline burned in an engine sends MORE than a gallon of water through the catalytic converter(s). It shouldn't be a problem.