Swapping Out the Catlytic Converter

[Davo53209]

I currently own a 98 Honda Civic Cx, with a catalytic converter that's attached directly to the manifold. At this point, it needs to be replaced, and there isn't a repair guide anywhere that can show me how to replace it.

Presently, I have both the upper and lower O2 sensors and along with the replacement part. From what I can tell, it looks like a simple bolt off and bolt on operation, however, I'd be interested to know, what sort of headaches might be lurking around the corner. For example, what would be the most efficient way to turn the rusty bolts without breaking off the heads? Or in addition, is there anything else to be concerned with?

Thanks.

[Hockey4mnhs]

im pretty sure that cats are very poisonous so you have to be carefull with it

[GasSavers_TomO]

The header nuts that are on the studs in the head are rarely ever a problem. you might get a stud that comes out with the nut, but it's not a problem, just bolt the nut/stud back in when installing the new part.

The two spring bolts that connect the Maniverter (or Catifold if you please) can snap. Either get replacement bolts from Honda directly or just go to the hardware store and get some bolts, nuts and washers big enough to hold the spring on the bolt.

Swapping out the part is straight up unbolt old part slide it out from the bottom of the car and bolt up the new one. It helps to jack up the front of the car as high as you can (that saves on back strain and clearance for eh old part to slide out).

Any questions, just post up and I'll help anyway I can.

[VetteOwner]

or you can just go to auto parts stores and get exhaust manifold bolts and springs (in the HELP section) cats arent "posionous" at all unless your the kind that goes around chewing on random engine parts...

best way to prevent broken bolts/rounded off bolts is to use a hex 6 sided socket.

they dont HAVE to be replaced if you dont have emmisions testing. get a reasonably cheap O2 simulator for the rear sensor.

[minic6]

Yes cats. can be quite harmful to your health. IF you break up a new style high concentrated platinum brick the dust can be very bad for you. We have to wear a resperator while working with them. Just swapping out a cat. is no problem. Trying to remove a brick is where you can have problems. Use penetrents to lube your bolts but as indicated they usually come apart OK.

[baddog671]

Originally Posted by VetteOwner

or you can just go to auto parts stores and get exhaust manifold bolts and springs (in the HELP section) cats arent "posionous" at all unless your the kind that goes around chewing on random engine parts...

best way to prevent broken bolts/rounded off bolts is to use a hex 6 sided socket.

they dont HAVE to be replaced if you dont have emmisions testing. get a reasonably cheap O2 simulator for the rear sensor.

Cats aren't posionous but they do contain heavy metals which are. Meaning, general handling of them wont harm you, but if you did something stupid like eat the insides or keep them against your skin for awhile, you'd become very sick

You know you can sell used cats? At our shop we sell the used ones to a guy for about 40 a piece, dunno what he does with them, but its something to do with those heavy metals.

And put anti-seize lube on those bolts when you replace them..

[Davo53209]

Being that the manifold is made of aluminum, I've also been wondering if heating up the rusty bolts with an oxygen tourch would be over kill. Also, would there be anything else that I would need to consider?

Thanks.

[VetteOwner]

just douse them in PB blaster and they should come out. after all aluminum doesnt rust!

and if your around/breathing the catylyst dust every day in an somewhat enclosed shop then it may be a concern. also the place you work wants to cover thier butts along with OSHA regulations so you cant come back and sue them for not warning you if you get diagosed with somehting related to breahing that dust. but once every 10 years isnt gonna do anything and most likely hes going to take it out throw it aside and install the new one. breathing large ammounts of any type of dust is bad(coal dust, saw dust, brake rotor dust, etc)...

[LeMangelo]

You did not say if bad O2 sensors ruined the cat.I would eliminate all causes of a cat failure before bolting on a new cat.Autozone has OBD2 scanner testing for free to check your work afterward.Breaking the O2 sensors loose is easier while everything else is still bolted together.The honeycomb can break up in a bad cat so do not have your face under the cat when you remove it because dust and pieces can fall out.I would have the fuel injectors cleaned off the car before putting on a new cat.You can send your injectors for testing and cleaning to http://www.witchhunter.com

[Davo53209]

I can tell you with absolute certainty that it is a bad catalytic converter. Up until recently, I suspected that it was a bad cat; but just like you suggested, I had already taken it to Autozone to have them hook up a code scanner. In fact, it was my hope to get off easily.

The problem was that the readings were always inconclusive. At the time, the most likely culprits seemed to be two bad O2 sensors, which seemed to concur with the opinions of everyone at Autozone .It was until recently when I'd changed both the upper and lower O2 sensors, that I finally got a precise reading off their code scanner, that difinitively indicated that it was a bad catalytic converter.