Catalyst Help!

GregR · Post by **GregR** » Sun May 07, 2006 9:14 pm

Well, Mac and I set about getting my janspeed off and the exige exhaust on the car at the weekend. How the hell MMC managed to get the undertray off for an oil change when Mac & me + angle-grinder + hammer + chisel (tried the alen key 1st

) couldn't after 15 mins I dont know

.

Anyhow, got the cat off to get the 'zorst in, but the mild steel bolts are rusted into the cat flanges. Many thanks to JJ for his help on the 'get me home' front

, but I now need help from someone that knows how to get 6 well rusted bolts out of a cat - anyone got the tools for the job? Tried 10 minutes of hammering to no avail.

Cheers in advance.

Greg

PS - many thanks to Mac for his time (10 am - 5 pm!), and the shots in the Macmobile for food & parts collection

Stephen · Post by **Stephen** » Sun May 07, 2006 9:23 pm

are the bolts in the cat not studs which are suppost to stay there?

Derek · Post by **Derek** » Sun May 07, 2006 9:23 pm

You will need a vice and a socket. Put the socket over the stud end of the bolt, and squash the threaded end and the socket together in the vice.

The pressure from the vice should push the threaded section off the flange and into the gap you've created inside the socket - IYSWIM!

Derek

mac · Post by **mac** » Sun May 07, 2006 9:32 pm

Stephen - your right they are studs, two of which sheared without too much presuasion during the opperation.

Derek - I know exactly what you mean, (adds vice to shopping list) although some heat might be needed to help it along.

Cheers

Mac

Stephen · Post by **Stephen** » Mon May 08, 2006 12:45 am

mac,
what you need is a press.
i ahve been thinking of rigging one up with a metal frame and a bottle jack.

robin · Post by **robin** » Mon May 08, 2006 7:12 am

They will come out with plenty of heat and if you are lucky they will press out the "socket" way. If not you will need to hacksaw the stud down to close too 10mm off the flange, then make a careful job and mark the center of each stud, then drill right through with successive larger drills until you have most of the stud metal removed. If you now heat & press as described above they should press out eventually.

Tempting though it is to pound with a punch and a hammer there are two reasons not to do this: (a) you bend the flange, (b) the shock can break up the catalyst honeycomb stuff leading to new cat required ...

Cheers,
Robin

P.S. Use copper slip on all bolts when putting the undertray on. That way they come off again

GregR · Post by **GregR** » Mon May 08, 2006 8:15 am

robin wrote:They will come out with plenty of heat and if you are lucky they will press out the "socket" way. If not you will need to hacksaw the stud down to close too 10mm off the flange, then make a careful job and mark the center of each stud, then drill right through with successive larger drills until you have most of the stud metal removed. If you now heat & press as described above they should press out eventually.

Tempting though it is to pound with a punch and a hammer there are two reasons not to do this: (a) you bend the flange, (b) the shock can break up the catalyst honeycomb stuff leading to new cat required ...

Cheers,
Robin

P.S. Use copper slip on all bolts when putting the undertray on. That way they come off again

Hmm - noticed lots of pretty coloured stuff falling out when I hit it with a hammer...

Looks like its CRP for the foreseeable then! Need to get hold of a heat source, all I have at the mo is my gas hob...

Cheers guys,

Greg

MacK · Post by **MacK** » Mon May 08, 2006 9:49 am

GregR wrote: Need to get hold of a heat source, all I have at the mo is my gas hob...

Cheers guys,

Greg

I have a couple of "heat sources" you could borrow...

John