How to get to the front catalytic converter nuts?

[runderwo]

What are your tips and tricks for getting to those front cat nuts behind the O2 sensor and getting them loose? What a PITA location...

 

[gmanpaint]

Jack it up, place on stands, remove the tire and attack it from the wheel well with wobble extensions, u-joint, and an air wrench. Still a pita, but doable.

 

[cougarmt]

Did you get your cat pipe pulled?
I've pulled my cats off a few times, and found the easiest way is by using a deep socket, and a long extension. The socket alone can be used on the bottom nut, while the extension is needed to reach up and over the Y-pipe and O2 sensor...from the front... May need a good soaking of penetrating oil, and a breaker bar, the first time.
When I first pulled mine, I busted one stud, so had to grind the head off the back of the cat flange (moto tool with griding disc worked well, then drill out the stud. Replaced it with a standard hex bolt, lock washer and nut. Just have to remember I need two different size sockets now! And you might want to use a little anti-seize compound on the threads when you reassemble; makes it a bit easier the next time.

 

[92exp4x4]

sawzalls make life much easier...

 

[cougarmt]

Unless you don't have a welder...yet... But hmmmm....guess I could always use a new tool!

 

[92exp4x4]

I just pulled a rearend for my Aerostar this weekend at the bone yard. My battery powered sawzall made it all possible. There was no way those 20 year old bolts were coming out easily, so it was my only quick solution. To bad I have to be more careful upon reinstallation.

Btw, welders are a great addition to any garage! I just got a Lincoln Mig about 6 months ago.

 

[Anime]

Using a drill with a cobalt bit.

On most 91-94's I've seen, the studs/nuts are rusted to the point they no longer resemble hex nuts, and often the Y-pipe and front cat pipe are fused together.

If the hex nuts are still turnable, twisting them until they snap the stud is an option, then bang out the stud.

I would definitely remove the Y-pipe and converter assembly for this as well.

Of course, it might be even easier to just install a set of headers with a Y-pipe and a new catalytic converter assembly.

 

[RedGuru]

Just did mine yesterday. Dropped the y-pipe and converter. To get them out together I removed the tranny mount cross member. A lot easier to grind off the studs when it's sitting on a bench.

 

[plasmosis]

re : magnaflow catalytic converter

My cusin owned the borla headerback, will a borla cat. conv. could bolt on as well.