How di I replace a catalytic convertor
Replacing a catalytic converter ranges from easy to moderate for most DIY mechanics. It is best to take off the entire exhaust system (not the exhaust manifold or headers) for a through inspection when doing this job as a bad catalytic converter is a sign that other parts of the exhaust system may be requiring replacement as well including the muffler(s) and tail pipe(s). Tenneco's Walker Muffler site has detailed schematics for both domestic and foreign cars. TRW Aftermarket may carry them too. (If you own a very expensive car; you plan on keeping for a long time , see about a stainless steel exhaust system... Borla, Remus, Supersprint, Bosal, and ANSA make many for foreign cars.) The other thing(s) to check and remove before taking the exhaust pipes off are the 1 or 2 Oxygen sensors... they will affect your gas mileage significantly. Unplug the wires to them and unscrew the front one and look at it. If it's filthy fouled replace it and the lower (if there are 2) one too... the information from both of them influences the car's ECM/ECU computer to adjust the air/fuel mixture.. (NGK, Beru, and Bosch make oxygen sensors for most cars.) Ensure you buy new exhaust pipe hangers and mounting bolts, if your hangers don't include them. Use Penetrating oil on a COLD exhaust system to help free up the bolts that join the lower part of the exhaust manifold to the first part of the exhaust system. Letting it sit overnight seems to work best. You may need a new gasket there so prepare and buy a new one to replace it. (When replacing, tight is good, too tight is bad as you may break off the stud or bolt.) IMPORTANT!!! Old catalytic converters need to be disposed of as hazardous waste as they contain several gridded wafers of electroplated platinum base metal. (Contact the new catalytic converter seller to see if they will take your old one or contact your city or county disposal office to see how to properly dispose of a used one.) Exhaust pipes typically fail where there are bends as the metal is stretched and thinner there... look for holes and rust. Typically, a ratchet set, rubber mallet and hacksaw may be required to cut a catalytic converter out and then crush the round inner sleeve remaining inside the exhaust pipes ends with a thin flat chisel, pulling it out of the "good" exhaust pipes using locking pliers (a.k.a. Vise Grips tm). (Alternatively, a rubber mallet may be used to strike the catalytic converter to break it loose from the exhaust pipe ends... DO NOT DO THIS if the catalytic converter is in the disintegration stage. Do Not use the mallet on the exhaust pipes as they will bend!) Use crocus cloth or sand paper to smooth the inside of the exhaust pipe connections and ensure by trial off the car that the new catalytic converter goes in the pipe ends easily before mounting the separate pieces on the car... terrible to learn it won't go in, due to carbon soot or rust when you're on your back underneath!
Oct 13, 2014 |
1999 Dodge Grand Caravan