Anyone that has changed the catalytic converters?

Moglocker

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Trying to change the mini cats ,how in the heck do you get the 4 catalytic converter bolts off?what tools helped you,thanks really appreciated-jeff
 
Seem to remember using penetrating oil, a super long extension with a swivel and a short socket. reached up from basically ground level and think I went between the frame and fender & frame and oil pan. Think there was a few choice words said at the time too.

Dont let the penetrating oil get on or near your o2 sensors if you plan on reusing them.

Pretty sure I figured next time im gonna buy the cheap swivel sockets at Harbor F next time I needed to remove them.
 
Crows feet wrench on a couple and some combination of wobble socket extensions and regular socket wrench extensions on the others.
 
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Personally I just torch off exhaust bolts and replace them...but I think Mopar used strange bolts on those. The 2004 Cherokee I did a head gasket on was a nightmare. I spent more time on the exhaust then I did replacing the head gasket.

Give me a 97 or 98...rest of them just get too damn complicated.

-Mac
 
Personally I just torch off exhaust bolts and replace them...but I think Mopar used strange bolts on those. The 2004 Cherokee I did a head gasket on was a nightmare. I spent more time on the exhaust then I did replacing the head gasket.

Give me a 97 or 98...rest of them just get too damn complicated.

-Mac

Wow they are tight,and really rusty,will most likely get new clips and bolts if they are still available.
 
You can wiggle your arm around the steering shaft etc and snug from up top, ratcheting wrench helps, a click at a time. From down below lay on your back with safety glasses on, 3/8 ratchet and some u-joints and extensions. Make a list of of your favorite cuss words and teach the kids.

If you are replacing the cats and down pipe, another hand helps. If not I looped a ratchet strap over the top of the engine and down around the exhaust. Cinched it up to hold things semi in place. Also be aware that getting the flange seals lined up may take some creativity depending on welding tolerances and shipping damage.

The nut is: 6506546AA Mopar Nut about $12ea

Be ready to fight an ongoing P2098 code every couple months after this. I think I need new nuts.
 
I used an impact driver with some long swivel-end extensions for most of them and a flexible extension for one of them. Pro-tip: hit them with penetrating oil (I used PB) two or three times over the course of the day before you try; spray a little, let it soak for a few hours, do it again..
 
It sucked as already mentioned by others. A wide variety of sockets, swivels, extensions etc. I used new bolts. I think I used stainless bolts if I remember correctly. I chased the threads on the "nuts" but used new bolts. There was some cussing but new ones been working fine.
 
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Do they require gaskets?

IIRC, no gaskets.

Swivel socket helps.

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I used to use extensions from below, till I realized I could use a ratcheting wrench from the side.
 
Trying to change the mini cats ,how in the heck do you get the 4 catalytic converter bolts off?what tools helped you,thanks really appreciated-jeff

I originally used a combo of extensions and combining wrenches for added torque.

Since the first removal, I’ve been able to remove and install them multiple times using a ratcheting wrench. I always lube the fasteners with high-temp nickel based anti-seize before install.
 
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I just did the job a few days ago. New clip nuts help. Swivel sockets help. Flange bolts help so you press them up with the socket. Longer bolts help, mine had some non OEM bolts which were too short to get both sides to start threads. The most forward bolt required an open end wrench making 1/8 turns to get torqued down. Not fun!
 
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