respecttheseven

is there a way anyone knows of?

RonKMiller

Not that I am aware of. What makes you think your cat is "dirty"? Most cats can last up to 100,000 miles before they need to be replaced, if you are running close to stock configuration.

Not trying to flame you, just curious why you would ask such a strange question without knowing more background info on car, problems, etc.

rzograbian

to clean or to clean out?? if you want to clean them out, you have to cut into them and remove the filter things.. i dont know if this is what you want

SNracing

get a downpipe, then you wont have to worry about it clogging. they go for like $250.

user 9348703

Get a 2 inch diameter rod and a sledge and clean it like that, never clog and looks like a real one hehe

SNracing

oops... you said cat, not pre-cat. well in that case there is always a high flow cat.

respecttheseven

thats because i meant cat. not pre-acat. thanx for everyone who thinks i am an idiot! lol... i build my car from scratch. it has a downpipe, but my smog pump went byebye and has thus dirtied up my cat(midpipe). so in order to keep my fd from detonation, i would liek to try and clean out the nasty stuff on my filter. and i cant bust it out unless i want to do a full ecu replacement. ! sigh, please if anyone knows what they are talkin bout that knows if there is a fuel additive or process to clean it out, drop me a line. ciao
chris

user 9348703

I think everyone is in a good NEW YEAR MOOD!

Anyway nothing that I know of, shouldnt be that bad to cause any problems. Maybe get a **** load of brake/parts cleaner and just start spraying. Actually hold that. Does the one in the US have freon in it? If so USE it, if not I might change that statement since you want it to dry up good first.

respecttheseven

jt thanx a bunch. i will try both of those options. sorry for being a grouch everyone! a loved one passed ,and i am entering a new life... ceers for 2004, lets make it a great year!
chris

David Beale

Don't put any fluids in there. The only way to clean out the cat. is to burn out the crud. The stuff left in there that doesn't burn can't be removed without damaging the cat. Best way is to force the air pump to work full time for an hour or two and drive on the highway. If your air pump has failed, you could replace it with a Corvette electric one or a stock one. Air (O2) is the only correct way to clean it out. Just make sure you don't overheat it when you do this.

doncojones

Yeah the cat works on a chemical reaction between bad exhaust gasses and platinum (bling bling, hence why cats are so expensive). As the name suggests, the platinum catalyzes (starts) a chemical reaction that causes the bad exhaust gasses to be converted into not-as-bad exhaust gasses. It's not really a filter that you can just clean with some solvent, as David above me has pointed out.

I just read that and I now have quotes from the movie 'Office Space' floating through my head, but you guys get the point.

RonKMiller

Like I said, there is no way to "clean out" a cat.

If you've ever cut one open before and looked at the ceramic or platinum matrix the deposits in there are literally cooked on at high temperature and impossible to remove under ANY circumstances. They are physically bonded to the surfaces. Cats are a "wear component" and usually have to be replaced at 100K or less. Over the years all of mine - no matter what the vehicle - seem to be pretty well toasted at 90K to the point that they are strangling the engine.

While the OEM cat is insanely expensive there is absolutely no reason you could not buy an aftermarket cat that could easily be fit in the same place with a little cutting and welding. They all are made and work the same.

You'll save about $600.00 over OEM, keep the environment cleaner, be a lot quieter (the cat deadens more sound than a muffler) and smell much better than running without one. You'll also be able to pass emissions and rejoin the human race...

doncojones

Ya know now that you mention it I should have realized there's no way to clean a cat. The catalyst in a chemical reaction is always used up so of course you would run out of it at some point.

Oh well, I'm an English major and I don't really pay attention to that kind of stuff on a regular basis.

wiblergt

i just removed my 60k mile stock cat if you are interested. it's going to the scrap yard in the next day or so... let me know.

Big Will

user 9348703

The thing was no one wanted to hear there is no way to clean a cat. He didnt feel comfortable driving it as is, so this would at least make him feel better about it.

Bang it on the ground a few times spray the spray IF IT has freon and a little bit of ***** will loosen and yippy he will drive it and it will be fine..

Hell I do ***** sometimes just to make me feel as though I AT LEAST TRIED, if something does break later on. Better then saying oh fruck it...

Know what i mean?

I am saying this with a smile of course....

RX7FAN

By the definition of a catalyst it is not used up in a chemical reaction. But since the engine puts out so much filth the Pt. plated surfaces get coated till the initiating surfaces are no longer converting the gasses. At this point your car may still run fine but your emmissions will suffer.. When the buildup starts to close off the exhaust passageways then your performance will suffer. In the lab I'm able to "burn-off" the coatings I get on my Pt. disks. Since the temps in that blast oven of a cat of ours where the coatings are deposited are so high I don't know if you can reach a Temperature that will burn off the coating without melting the housing or even the Cat itself.

Just don't buy something in a bottle that says it will clean up your cats...

doncojones

Yup, I need to stop telling myself I know anything about chemistry.

Larz

Hmmmm, interesting thought. Not all that relevant to me, but provocative.

RX7FAN

I'm using a Cat made for Big block flow it may not last as long as a Rotary specific cat but it's 1/5 the price

Roar 629

try those muffler shop.. ask them.. i gues they have better idea.. but i would recommand what david say above if u dun want them to touch YO car. new year!

respecttheseven

hey guys, thanx for all of your input. this has turned out to be a great subject. here is the question that lies ahead now: will my car run ok with an aftermarket cat. i know the ecu requiers a certain amount of backpressure to maintain is regularaity and prevent boost spikes, so is the only reason i dont just bust the center out to prevent boost spikes? i know i need a new ecu if i replace the midpipe to an after market one.. whatcha think....?

potatochobit

iTrader: (1)

rx7 fan is it a bolt in or did u cut and weld? 1/5 price works for me if they last a year or 2, heh.

doncojones

Well presumably the other reason you shouldn't "just bust the center out" is to prevent your car from spewing raw exhaust out into the atmosphere, but who cares about that right?

A few companies make replacement midpipes with "high flow" catalysts in them. How much your backpressure will be reduced when installing one kind of depends on what else you've done with your exhaust.