I guess we all stumble onto islands of expertise. Rick Yukon used to tell me that for some reason, the only islands of expertise that anyone seems to care about with him were the ones where he found ways of saving a few hundred bucks, or ways of spending a few million bucks.
I have found myself in the same position as Professor Yukon, albeit with neither his taste for alcohol nor the kind of debt where both a 300 stone enforcer and a 120 pound manager of that enforcer end up paying the debt-holder a visit.
For some odd reason, I have discovered that I have an expertise in getting vehicles back on the road after two of these conditions have been met:
- The vehicle has experienced the failure or loss of its catalytic converter, resulting in an engine that sounds like it has community pneumonia acquired from an evening in the company of philanthropists at the John F. Kennedy Center for the Performing Arts (failure of cat), or alternatively sounds like some dude in front of a biker bar with a Fat Boy and twenty years of hard-banging with his new 32-year-old wife (loss, aka theft of cat),
- Owner of vehicle has neither the inclination to involve her insurance company, nor the material wealth to buy purchase a new OEM catalytic converter and install it himself. (The linguistic genders of these two hypothetical people could be reversed, if desired.)
When I talk about this subject, people who have found themselves described as above tend to seek me out in their desperation, and hopelessness. And like a calm, furry angel, like a comforting Saint Bernhard mixed with a Bloodhound, like your own mommy and daddy who came to tuck you into your bed at night instead of beat you while under your blankies from a dead nuts money dream about a sweet-ass set of Hotwheels and tracks … like the gentle human that I am, these miserable people come to me and I give them the words that bring them peace.
What do I tell them, to earn their trust and their love?
I tell them that it’s going to be okay.
I tell them that they might not need the expensive catalytic converter that is compatible with the California Air Resources Board, maybe they live in a state where they can just buy the EPA-compliant catalytic converter for $150 or so, and put it on themselves, get their car on the road, after some fucking asshole stole the cat off of their only damned vehicle, that gossamer thread of connection that they have between a happy and reasonably comfortable life and an hella miserable life. Maybe things are that bad? Pull the front of the car up on the tallest curb you can find, get some tools, pull off the broken cat and put up a new one, probably made in China, but compliant with the EPA standards and no more difficult to replace than straight-piping it, because even if your state allows a straight pipe, it isn’t going to save you that more more money than just putting in a compatible part, and not punching a hole in your cat because then it might not pass emissions.
But no, they say? They live in one of these states?
- American Samoa
- California
- Connecticut
- Colorado
- Delaware
- Guam
- Maine
- Maryland
- Massachusetts
- Nevada
- New Jersey
- New Mexico
- New York
- Oregon
- Pennsylvania
- Puerto Rico
- Rhode Island
- Saipan and Northern Mariana Islands
- U.S. Virgin Islands
- Vermont
- Virginia
- Washington
- Washington D.C.
If you live in one of these states, and you just found out that you need a new cat, due to failure or loss, you now belong to one of two catagories:
- You are not worried and your life has not become appreciably worse. These people have vehicle insurance (loss or theft of their cat) or they can afford a substantial bill from their local mechanic.
- You are an emotional mess, you curse the motherfucker who stole your cat, you curse the person who owned your vehicle before you for clearly damaging your cat that was supposed to last the life of the vehicle, at least that’s what the sales agent at the used car lot told you. You don’t know if it even worth replacing the cat at that cost just to pass the emissions test and keep it registered, and you have seriously considered selling your baby and buying another used car that won’t break down so often.
Still reading? You couldn’t resist some of my vehicular love, could you? You just couldn’t keep away from my mechanical loins, could ya?
Of course you couldn’t. I offer salvation.
First off, check the price of some CARB cats online. They aren’t cheap, but if you are half-decent with some metal fabrication, you can get a universal CARB-compliant cat for a couple hundred bucks or so, cut off the old cat right at the ceramic cartridges, weld in the universal cat, then do what you need to do to connect to your bolt flanges, so the next poor sap can unbolt the cursed thing and install an OEM when he or she pulls a Bedford-Stuyvesant on your junker and turns it into a valuable classic. You will pass by her, your angel, she will be on West Olympic Boulevard near Koreatown. Her new owners will love her in a way that you then wished you could have loved her.
And you can love her like that, even if your skills of being a mechanic are half-assed and your only gnat’s dick better than broke.
So, if your cat was stolen, and you can’t go with insurance, you should be able to put in a CARB-compliant catalytic converter yourself for less than $800, maybe even less than $400.
But if your cat just died, and has your engine sounding like it finally decided to quit vaping and smoking, wheezing and sputtering like an asthmatic doing the Unsanctioned 250, and if even $400 is a bit steep for you, then you have come to the right place, and I offer you salvation.
For the low price of just $25, plus a bit of elbow grease, you can possibly clean out your clogged cat and get your car back on the road. Now, if your engine still runs pretty well, and you’re just getting an exhaust error code, then might be able to clean out your cat with some of that stuff that you pour in the tank. Or maybe two or three of those. But if your cat is so clogged that it has impacted the performance of your engine, then you shouldn’t expect to be able to fix that with something that you pour into your gas tank. You will need to take the cat off of the vehicle, and clean it the industrial way, the way that air pollution engineers clean their expensive commercial cats.
Still reading?
It isn’t that tough. But it will take you a couple days, during which you won’t be able to drive your car. Don’t be temped to drive the car without the cat, regardless how desperately you need to get to the Kennedy Center and have to tip the valet $5 for having to drive your death trap to the parking spot. Just don’t drive it. The hot exhaust might choke you death, or worse, burn up some of your engine wiring, at which point, if you hadn’t been lucky enough to stumble on the likes of me, you would have no idea that this is fixable too.
Get the vehicle up on ramps or a tall curb. Block the back wheels, pull up the emergency brake, be sure the vehicle is in park. Wait for the vehicle to cool down so you can take off the cat without getting burned. Get a headlamp and take some photos with your camera of everything that you are about to remove. Spray some PB Blaster on the bolts that you need to remove. Find the connection to the downstream oxygen sensor, struggle with that for about half an hour to disconnect the oxygen sensor harness from the wiring connection. Don’t break it, use WD-40 if necessary, you can clean it later with some electronics and contact cleaner. If you can, remove the oxygen sensor. If you can’t get to it, just be careful of it when you remove the cat, and you will take the oxygen sensor out later.
Remove the bolts that hold the cat to the exhaust manifold on one end, and the resonator on the other end.
If you are lucky, the bolts came off. If you are less than lucky, you found yourself banging away on it with a hammer and a persuader pipe around the end of your breaker bar. If you are slightly more lucky, your compressor and your pneumatic impact wrench proved their value, once again. If you are ambiguously lucky, then you are now married to the redneck fellow that you recruited to do all of this and get your car back on the road. The ambiguously lucky find themselves in two categories;
- In the process of getting a decent job so that she can buy a new vehicle and not have to rely on the dirty brute anymore to keep her mobile. You will deal with the emotional fallout the way you usually do; with a string of failed romances and some substances.
- Married to the dirty brute, and actually kinda flippin’ happy with the filthy bastard, because while anyone can love a redneck when their car breaks down, she found out that the idiot can also rub her neck and her feet and make her a dinner and actually take car of her the way no other man has ever taken care of her.
You get off the cat, and then if it’s a warm summer day, you get the garden hose and get to work, if it’s cold and icy then you drag the filthy brute up to the bathtub or the shower and then get to work. Before we get the shopping list, find an old plastic supermarket bag, or a whole lot of used plastic food wrap and plug up the little hole on the side for the oxygen sensor. If you are lucky enough to have one of those small cats that doesn’t have the oxygen sensor hole, you can skip that step.
Before you start, get a flashlight and your phone and take a photo of the front and back surface of the ceramic honeycomb inside of the cat. You will want to compare the before and after images of the ceramic. The ceramic honeycomb should cover the whole surface of the catalytic material. If you see a whole drilled into the center, don’t waste your time with the rest of this, someone already straight-piped the cat, and you will need to replace the cat if you want to stay compliant with the air pollution laws, depending on your State.
Next, the first cleaning step is cheap, just run some water through the cat. It might be so clogged that the water takes minutes or longer to move through. Do what you can, the real cleaning happens next …
The stuff you will need to clean out that cat isn’t cheap, or at least, it isn’t cheap enough that you will want to buy ten bottles of the stuff. To keep this adventure around $25, you will need to just get enough cleaning stuff to fill up the cat, rather than fill up a bucket or trough to soak the cat. You should be able to fill up most cats with a gallon each of the cleaner. To do that, and let it soak for a few hours, you will need to cover up one of the ends and then stand the cat up in a bucket to catch the stuff that gradually leaks out. Usually, the better end to plug up is the tail of the cat that goes into the resonator, but either end will work if the flange is amenable to clamping. Get a big piece of plastic food wrap, double it over, double it again, so you have four layers. Use rubber bands or a bungee, and if necessary, keep it tight with a hose clamp. Put on some rubber gloves, and possibly even eye protection, close that gorgeous thing you call a pouty little mouth. Then put the plugged end of the cat downward in the bucket and the open end facing up, you will pour the cleaner into the open end.
Sodium Hydroxide is the alkaline cleaner of choice for air pollution engineers who have to clean their industrial cats. There is Sodium Hydroxide in oven cleaner and in drain cleaner. The drain cleaner is usually cheaper. With the bucket in the shower or tub, pour the drain cleaner into the upright end of the cat, so you fill it up like a flower vase. One big bottle might be enough, or you might need a second one. Depending on the size of your cat, it will swallow about a gallon of drain cleaner. Let that soak for about four hours at least, or overnight better.
Depending on how tight you covered the end, you drain cleaner is either still mostly in the cat, or mostly in the bucket. Take off the end, let the Hydroxide drain out into the bucket. If the drain cleaner is really filthy, you might want to dump it and put in a fresh batch. If it isn’t yet too filthy, (perhaps it drained through your leaky plug a little bit too fast) then you can put the plug back on and repeat. You should try to get the cat material to soak in the cleaner for at least four hours.
Next, be sure the plug is off, and flush out the cat with warm water. You will likely notice that the water flows through the cleaner cat a good bit better than a dirty cat. Be sure to put in the water from each end, to help dislodge more gunk. When the water flows clean and the bubbling has stopped, drain the water, put the plug back on.
Next, do the same thing, but with Acetic Acid. A cheap way to get Acetic Acid is with white vinegar. Buy a couple of the gallon jugs if they are cheap enough. Again, put the vinegar into the upright cat and let it soak for a few four hours. No matter how well you cleaned out the cat, you will undoubtedly still see some bubbles in the vinegar as you pour. That is the acid reacting with the bits of remaining sodium hydroxide from the drain cleaner. If the bubbling is too intense, get out of the room and turn on the vent fan, you don’t want to gas yourself with whatever byproducts have reacted in there. Wait a few hours, pull off the plug, drain the vinegar into a bucket. If it is clean, you can reuse for another round of cleaning, if it is slimy yellow like the ejaculate of a toad, then perhaps you should consider discarding it and use a fresh bottle for the next round of cleaning.
Flush again with water. Repeat the process of hydroxide-water-acid as many times as needed until water flows reasonably through your cat. It will never flow freely, those honeycomb channels are really narrow, and the surface tension in each little capillary is sufficiently high to slow the flow of the water.
Very important safety: Do not let the used or new drain cleaner come into contact with the used or new vinegar. They will react. If you flush them both down the same drain, first pour the dirty drain cleaner, rinse with a good bit of water, then pour the dirty vinegar down.
Give your cat a final flush from both end, stand it up so the last bits of water can drain onto the floor.
Now you will need to blow it out with air.
Be sure your oxygen sensor hole is still plugged. Put back on the end plug made of plastic food wrap and your hose clamp or rubber bands. Make a tiny hole in the center of the plastic. This time, set the cat so the plugged end faces up. Use an air compressor to blow out as much water as possible through the cat. If you don’t have access to an air compressor, you can make the hole bigger and use the cold setting on a blow dryer. Keep this going until no more water drips out of the cat.
Use your flashlight and your phone to take a photo of the surface of the catalytic honeycomb. It should look pretty damned good, and put a smile on your face.
Clean your downstream oxygen sensor with some electronics cleaner, put it back into the cat, if necessary. Reinstall the cat into your car. It is very likely you will now enter a new place of agony and anguish as you try to remount the fucker back into place. The bolt springs are there for a reason though just keep at it, and you will either get it, or as previously mentioned, you will find yourself married to that redneck fellow with those two paths in front of you.
Reconnect any brackets, clean and reconnect the oxygen sensor connection. And you should plan ahead and purchase a new packing gasket, which fits between the exhaust manifold and your cat. It is special stuff, it’s made of compressed wire and it is designed to expand and contract properly with changes in heat, to keep the exhaust gasses where they belong.
If you want numbers, you can remove the upstream oxygen sensor and measure the pressure at idle and throttle to see if your cat is mostly clear. If you cleaned it well, and if your cat hasn’t been damaged your clogged-cat conditions should disappear for at least a few months, or hopefully longer. If you get good at this process, you might prefer to do it every year or two, to keep your vehicle happy.
At this point, many expert mechanics have resisted my charms and have decided that the catalytic material has been sufficiently depleted in the cat that these cleaning methods simply polish a turd.
Maybe. You do you.
But as an air pollution physicist, with some knowledge in this area, I happen to know that catalysts do not react all that well with soot. They react with volatile gasses and unstable molecular compounds of oxygen, nitrogen and carbon. So if your cat is coated in a layer of soot and volatiles, that soot and those volatiles will also reasonably protect that catalytic surface. In other words, your oven might be truly dirty, but the enamel under it is likely in fairly good shape, if you are willing to spend some time and some elbow grease cleaning it with the sodium hydroxide in your oven cleaner.
And cry me a river over the integrity of the cat …
The reality of these cats is that they have become a revenue source for the industry. And the objective of a skatepunk molecular physicist such as myself is to keep the last few remnants of wealth for my bothers and sisters, rather than the vehicle industry.
Bothers, sisters, until you can afford to buy a new a cat, listen to the calming tones of my voice and know that Uncle Ukon cares for you; you have a decent shot of keeping your ride on the road and your life together if you clean out your cat. Plus, there are a lot of really friendly rednecks of all skin tones, ethnicities and genders who would love to be married to you, and might only cheat on you with a boat, a dirtbike, an snowmobile, a skateboard or a charming performance vehicle.