Catalytic converter cleaning...would you do it?
 

Would you clean yer catalytic converter if there was a low cost and easy process available? Kinda like cleaning the MAF sensor versus replacing it because it was dirty.

Had a little time so I built my own catalytic converter washer. I've named it the CatWasher. It's still a work in progress and I should be able to test and document it's cleaning efficiency tomorrow on my own 370,000 mile catalytic converter. :D
http://i677.photobucket.com/albums/v...s/IMG_1297.jpg

It has enough pressure to shoot a continuous liquid stream over 10' in the air.
http://i677.photobucket.com/albums/v...s/IMG_1267.jpg

I've seen rotted out cats but never a dirty one... and since dropping the exhaust is so much fun I'm thinking this would really be one of those things where "if it ain't broke, don't fix it" applies.

I am not sure but doesn't water kill cat convertor? I bought 2 90's F250 that been sat on gravel for 7 years. Was surprised it didn't rusty badly. When we saw off cat convertor it was full of water mix cermanic fall out.

I think thin metal wire poke though cat convertor sound good idea.

I've never had a nice car (until now) and don't live in a DEQ area, so my cat gets the ramrod treatment when the car throws codes. This results in a louder exhaust note, but well worth the extra couple mpg.

Considering the cost of a new catalytic converter, I would not try it. The high heat should keep it clean..I guess.

Another vote for "If it ain't broke, don't fix it".

So far...no cleaning. Got it. Still gonna press forward with my project. :D

Cleaning process should work on O2 sensors as well...but since they are cheap enough (less than $100 each), why bother. ;)

Why wait until the catalytic converter throws codes if yer gitting instant higher MPG and HP? When you git a brand new (or new to you) car, just drop it the converter down (bolts aren't even rusty yet on a new car) and bust that sucker out! Better MPG and HP over the stock numbers! ;)

High heat doesn't keep the converter clean...really. Build up will eventually clog the converter as I believe it doesn't happen in a linear fashion. Same thing goes fer air and oil filters.

I'm not using just water...I'm using a heated weak ~0.1 M citric acid and oxalic acid solution that I'm gonna cycle through the catalytic converter. I haven't see what the grid of a converter looks after 380,000 miles yet... I did find this on the internet...not sure on the mileage or what brand/type of gasoline that was used on it. ;)
http://mkrd.info/uploads/images/audi..._before_sm.jpg

Last I checked, a universal weld in yourself (or use clamps) was less than $100 too.

Converter media definitely a good coating but only a few squares clogged up...at least it's nothing like that other piccie. :D

380,000 mile converter...
http://i677.photobucket.com/albums/v...s/IMG_1299.jpg

Closer view of the grid...
http://i677.photobucket.com/albums/v...s/IMG_1301.jpg

You'll find out the hard way (unless you do some internet searching) that the universal converters don't work as well on Toyota vehicles as the OEM has more precious metals to do the work. Try it and see... ;)

I'm sure a straight pipe is even cheaper than that... :D

not in over regulated California, unfortunately... take the cost of any quality '49-state' cat , and add about $125 to the price. You won't find an out of state parts house that will ship a 49 state cat to California, or risk a huge federal fine. Same with an instal shop. They can only instal replacement cats with a CARB number on them. I recently looked at all possible angles.

Supposedly, these new and improved California catalytic converters have a higher platinum content, burn that many more leftover unburned hydro carbons and convert that much more NOx (I guess) for cleaner emissions out the tailpipe. BTW, Cali has decreased the allowable emission out the tailpipe over the years for older cars, as a way of getting older cars off the road. A new and improved cat might clean up an older car enough to now pass smog testing. The higher platinum content, the lower production numbers, and the CARB tracking were sited by a manufacture's rep as the price jump justification.

I'm only moaning about it because I just went through this a year ago, felt like I'd lost my virginity and was tossed out into the street after the smog and the muffler shop had their filthy way with me and my wallet :eek:

Washing: If it were me, before I invested much time in the concept, I'd research the various failure mechanisms by which catalytic converters stop being effective. The reactive metals in the ceramic might be only a coating for instance. If this is the case, and the failure is that the coating has fallen off, no amount or washing will rejuvenate the finicky little device.

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

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

Exactly... :D

After 30 minutes...
http://i677.photobucket.com/albums/v...s/IMG_1323.jpg

Residue at the bottom of the CatWasher...
http://i677.photobucket.com/albums/v...s/IMG_1324.jpg

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! :D

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.

After 2 hours of cleaning and backflushed with tap water...
http://i677.photobucket.com/albums/v...s/IMG_1337.jpg
http://i677.photobucket.com/albums/v...s/IMG_1338.jpg
http://i677.photobucket.com/albums/v...s/IMG_1339.jpg

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! :D

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... ;)

http://i677.photobucket.com/albums/v...s/IMG_1342.jpg
http://i677.photobucket.com/albums/v...s/IMG_1343.jpg
http://i677.photobucket.com/albums/v...s/IMG_1344.jpg

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. :D

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. :D

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. ;)

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

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.

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. :thumbup:

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

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.

Fergot to mention...chemical cost to clean the converter was under $10 fer 6 gallons of solution...cheaper if you don't use that much. Stuff you can find at yer local stores, too. ;)

Would've cleaned my O2 sensors, too...but I had already shipped those off to someone else last year. :(

I see two problems with this as a business model (in the US):

1. In 49 states, a replacement "universal" cat can be had for roughly $100. This means you'd have to undercut that price for your service...not a whole lot of profit.

2. In CA, you'd be installing a "used" cat on a vehicle...which is prohibited by CARB rules. You'd have to convince them that a "reconditioned" cat is the equivalent of a new one...a task that I'd guess falls somewhere between "extremely arduous" and "impossible."

I'll go with post 2 Frank Lee says if it aint broke dont fix it. and I might add if it is, replace it with new its already gonabe a pain in the tail pipe.

2. I wouldn't be selling any converters as I would not be buying it in the first place. When you have someone washes the dirt off yer car...are they selling you a used car when they git done washing it? I'm not replacing the converter...only attempting to clean it...so it would still be the same ORIGINAL OEM converter they owned before the cleaning process. In California, are you allowed to clean yer MAF or do you have to buy a new one every time it's dirty?

I didn't find anything in the CARB that specifically prohibits the cleaning of the converter...only the replacement of the converter with non-approved converters (which some aftermarket converters were rescinded as of Jan 10, 2012 (http://www.arb.ca.gov/msprog/aftermktcat/catrescind.pdf). If the converter on there is already approved, cleaning it will not change the approval status. The only way it would be rejected is when the converter is no longer performing up to the emissions standards set forth by the California Air Pollution Control Laws, California Air Quality Legislation, and the Federal Clean Air Act.

When yer vehicle fails an emissions test, does the inspector force you to relinquish yer vehicle to them on the spot? When you bring it back fer a second test, what do they do? As long as you pass the visual and emissions test...that's all that really matters to them. If you stuck some "additive" in yer gas tank and went driving fer 100 miles in order to "clean" yer converter, do you tell them that's what you did? Does the inspector ask you what you did to improve on the emissions test? I don't believe they will as their machine will tell them if you pass or not.

1. Show me a receipt of someone who had their converter replaced fer $100 or more and tell them they could've cleaned their original converter (provided it wasn't broken or rusted out) fer a cheaper price and see which way they vote. ;)

Not a problem with that train of thought. Do you have the same thought with changing the air filter or oil and filter on yer engine...or do you wait until the engine starts having problems? Having a "clean" air filter on modern cars is just a waste and won't improve yer mileage at all. The modern spin-on oil filters weren't introduced on automotive engines until 1955. Do you clean yer windows periodically or wait until it's completely covered over in dirt/bugs/oil before you replace the windshield? ;)

It only took me about 5 minutes (taking my time) to remove my converter after removing my belly pan and drove it up on my car ramps. Four bolts, two nuts (O2 sensor), and two rubber supports and it was out. I know others might take hours longer...especially if yer in the rust belt. :D

Would you take the chance on cleaning yer converter and O2 sensors if it saved you money from replacing them if they were in still in good condition? Would you spend $5 to try? I'm guessing you'd be happier at spending $100 or more instead... :D

A real test on the efficiency of yer converter is to do an emissions test. Hours of operation or mileage would be a better indicator than time.

Here's how to remove the converter on yer 2001 Echo... ;)
How do you replace the catalytic converter on a 2001 Toyota Echo

First of all I.m no expert on cats, What I have seen is that the matrix in the converter is fragile and complex,ya don't beat on it when its plugged or it turns to powder. what is going to happen to it when ya liquid/flow clean the thing. I hope it works and you make your fortune

I ran the solution through my $1600 (new, MSRP) converter at the rate of about 5 gallons per minute at a pretty good pressure fer about 4 hours. Not sure how much pressure as I don't have the correct tools to measure it but it will shoot a solid stream of water over 10' tall. My converter didn't collapse or crumble...but I know that's only one converter and there are probably ones out there that could easily crumble based on the abuse that it went through. It would be interesting to collect data on which ones do crumble down and the background on them. :D

Not sure if I will make money on this...I'm just doing this fer fun to see what will happen to the industry. I'm sure someone's gonna make a ton of money... ;)

Doing more research on O2 sensors...they most likely won't fail because of gitting coated but more from the heat cycling of the sensor itself.

I did git an offer to clean a pair of Tundra converters from California but with shipping back and forth, it would've been more cost effective fer him to build his own CatWasher and clean them himself...and there would be less chances fer his converters to git damaged. :D

I have never used catalytic converter for cleaning purpose. What is your review about the product is it effective and efficient?

This reminds me of the Scotty Kilmer episode on youtube about cleaning a catalytic converter...

http://www.youtube.com/watch?v=5icTmYItwiE

OP if you are still around.....Did you soak the cat first or did you just run it though the washer?

Fun thread. Thanks.

Any thoughts on "performance" since the cleaning?

.

Yeah...Scotty Kilmer is a funny one. I guess from what we understand what "washing" is...I guess this would technically be washing the converter. No, washing it with soap will not remove the baked on deposits off of the catalyst. :(

I didn't soak the converter prior to engaging the pump. I just let the solution do it's job. Kinda like what Lime-A-Way does to lime deposits in yer bathroom. :D

I currently have over 41,000 miles (close to 2 years since cleaning) on my "cleaned" converter without any performance issues or codes. The mileage on my truck and converter is over 412,000 miles. ;)