View Full Version : Catalytic Stud Question?


grinn253
02-27-2007, 01:13 AM
Hello,

While removing the Cat a few days ago, the 3 bolts (near the engine side) were stuck pretty good. So i used some "Liquid Wrench" as well as "PB Blaster" (could not find Kroil oil locally :( ). After letting the Cat sit for 2 nights and respraying the bolts periodically, the nuts were still stuck on. I now ventured on to a butane torch to heat up the nuts. This somewhat worked, as the nuts fell off...taking a piece of the bolt with them. :crazy: Doh! At least i was able to get the Cat off.

Question is, does the 3 bolts that are on the Cat come off, or are the welded on? They are still stuck on. May I have some suggestions on how to remove the bolts. :) I recall 'drilling them out' is what others have used, is this true? What type of drill bit is necessary?

Thanks for everyone's time.
Edgardo

The three bolts I am referring to are in the attached pic. (pix courtesy of Swoope from another thread)

http://www.rx8club.com/attachment.php?attachmentid=94772

lurch519
02-27-2007, 01:33 AM
you can bang em out, just be careful

TeamRX8
02-27-2007, 09:09 AM
they fit like splined wheel studs, knock them out with a hammer

grinn253
02-27-2007, 04:39 PM
Thanks all!

By the way my local Mazda dealership wants ~$6.50 per bolt! Does anyone suppose I can use 'normal' and not 'splined' type bolts for this application? (Automotive grade) So that when i need to remove the Cat again I don't run into this issue again.

Thanks!
Edgardo

Mazda-Rati
02-27-2007, 04:54 PM
yeah. just go to the hardware store a get 3 bolts, 3 nuts, 3 washers and 3 lock washers. It'll work fine. This is how I did it when one of those nuts sheared off with some of the thread. I haven't had any problems since

grinn253
02-28-2007, 01:33 AM
Thanks all!

Using my cousins 4lb hammer did the trick. Thanks for all the suggestions. Here are some pix:

http://www.rx8club.com/attachment.php?attachmentid=94846
http://www.rx8club.com/attachment.php?attachmentid=94845

Mazda-Rati
02-28-2007, 06:05 AM
^nothin like a good ol' baby beater to do the trick!

4 years to Supercharge
10-01-2007, 02:20 PM
I just tapped mine out today. :D:

Will be replacing with stainless bolts and it will make swapping the cat out much, much easier.

:cool:

:icon_tup:

Crazy Rx-8 Driver
10-06-2007, 10:10 PM
where did those bolts on the Cat connected to?

cajunrx8
10-06-2007, 10:42 PM
Also make sure to add a little never-sieze to the threads. It will make it easier if you need to remove later.

4 years to Supercharge
10-07-2007, 05:21 AM
where did those bolts on the Cat connected to?

The header side. ;)