Cat Bolts

[Osprey6010]

Hi all, attached are pictures of the nuts on my catalytic converter, which as you can see are made of pure rust. just trying to think of how i get them off to be honest. I've tried impact drivers, sockets with a copper hammer, breaker bars, etc. I do have a blow torch on the way which should help.

Any other ideas please shout them, I'm not expecting to have the bolt out usable again, it will most likely snap.

 

[caius]

Looks similar to the exhaust bolts I had to remove on the 2.5i. I ended up cutting them off with a Dremel and many cutting discs, was the only thing I could get under there to cut them in any reasonable amount of time.

 

[Osprey6010]

That's a shout. I think I can get hold of an angle grinder for a day. I assume you cut the bolts for the outside, not inbetween the cat and the exhuast manifold?

 

[PDJ]

Mine are Stainless steel
Another bonus for the next owner

You may need to take the exhaust down in a larger section and cut/grind them off and then replace the bolts and refit

 

[RMB]

That's a shout. I think I can get hold of an angle grinder for a day. I assume you cut the bolts for the outside, not inbetween the cat and the exhuast manifold?

I imagine on the outside as there will be a gasket in between that would be destroyed and then it would leak, no?
I had to have mine cut off and new nuts and gaskets after a very slight leak advisory on my mot.

 

[TriggerFish]

You'll struggle with an angle grinder for access - if you can get a Dremel, life will be easier.

What I did was cut the heads off (or just tightened them until they snap), and then remove the exhaust out of the way.

Then you can punch out the old studs (I've seen people cut a slit into the flange to relieve the hold on the stud), and replace with new. I went for stainless bolts and brass nuts, so they won't ever do this again. A little bit more money, but it'll save time/garage fees in the future!

 

[Osprey6010]

Yep, the new cat came with a gasket and new nuts and bolts which is useful. I've got one of those multisaws with a metal blade on, I'll give that a go first as I don't have a dremel. But tightening them until they snap is a shout.

Thanks for all the help I'll keep you updated

 

[Nick W]

Remove to a bench, use a hammer and small sharp chisel and either split or chip off the nuts, the hammering may even break some bonds. Then use a punch to drive the bolts out. There's no harm in using penetrating oil and or heat either. All much safer than any mechanical saws or discs.

 

[Osprey6010]

Got the 3 lower one off, just managed to twist and snap the bolt, last one is giving me a bit if grief, but that's a good idea, thanks. I'll try it now

Remove to a bench, use a hammer and small sharp chisel and either split or chip off the nuts, the hammering may even break some bonds. Then use a punch to drive the bolts out. There's no harm in using penetrating oil and or heat either. All much safer than any mechanical saws or discs.

 

[Osprey6010]

Got it off, thanks for the help.

Quick side question, is it dangerous to start it without a cat? I'm curious to see how loud it is