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ZeNiTh-PbArM · Posted: Mon Jun 02, 2003 6:31 am Post subject: rusted catalyst

hi everyone!

My beloved 33 (1.3ie Imola) has a dead catalyst : the rust has disintegrated some of the welding and metal. i had already patched some of the holes with "gun gum", sheet metal and wire.
now i think the damage is done beyond repair. the problem is, the part costs around 600 euros, which is a lot of money, and i can't reasonably afford it.
I've tried many Alfa dealers as well as some aftermarket specialists but prices are the same...
i wonder if it's possible to adapt the exhaust from another 33 (non catalyst), the exhaust manifold not being the same, to be able to bring my 33 back on the road ; i would have to weld a nut for the lambda sond.
has any of you done this before? does it work well? or do you have any suggestions, comments, or other ideas?

thanks for your help

regards,
zp

BILL · Posted: Mon Jun 02, 2003 7:20 am Post subject: DONT TAKE THE CAT OFF

Its vary dangerus for your health and for the others to use unleaded with no cat and i think its illigal in many countrys

Marcin · Posted: Mon Jun 02, 2003 11:01 am Post subject:

Hi zp,

where do you live? Here (in the Netherlands) it's possible to get a new cat for about 290euros, I recently checked. You can remove your cat for sure, but it depends on your country's law. If you have an obligatory technical checkup every year (like MOT in England or APK in Holland) your car might fail the emission test without a cat. By the way, mine has a cat and still failed it, it pisses me off Evil or Very Mad

Good luck

Marcin

ChrisC · Alfa Sprint Joined: 13 Mar 2003 Posts: 152 Location: Frome

Plenty of cars pass emissions without cats, including 33s. Put in a straight pipe, or if it absolutely has to have a cat, cut open a cat box and weld in a straight pipe through the center, then seal it up again.
_________________
Alfa Sprint QV - Gone to a better home and in happier health for it
Silver Lancia Beta HPE Volumex - under restoration

James Granger · Alfa 33 Joined: 10 Apr 2003 Posts: 302

Our 33 has no Cat and it managed to pass the stringent Dutch APK/MOT emissions test, despite being stored for 4 years. I was very relieved!

ZeNiTh-PbArM · Posted: Tue Jun 03, 2003 5:32 pm Post subject: re : how do i suppress the cat?

hi everyone!

thanks for your answers!

i'd like to know how you managed to somehow remove the cat? i've been unable to find any supplier for a straight steel tube, and i can't re-use mine after removing the ceramics inside because it's rusted beyond repair.

did you use another manifold/muffler? for me emissions tests are not a big issue since my car runs perfectly.

thanks for your help

regards,
zp

James Granger · Alfa 33 Joined: 10 Apr 2003 Posts: 302

Our car is Belgian spec (engine code 30753), thus didn't have a Cat originally. It is should be possible to replace your Cat with the alternative part. Where is the Cat exactly; is it behind the Lambda probe as a separate section?

Marcin · Posted: Wed Jun 04, 2003 9:04 am Post subject:

Yep,

it's behind the lambda probe, looks like a muffler. Can't miss it. However I would think that if your car hasn't got a cat, then it would have an middle muffler instead.

Marcin

ZeNiTh-PbArM · Posted: Wed Jun 04, 2003 3:15 pm Post subject: re : cat

hi

as far as i know, your car should be fitted with a cat.
For 33s fitted with cats, the exhaust manifold is different (front and rear cylinders associated like on the 145).
The manifold connects to the cat with a 3-bolt triangular plate (the tube is inserted in a muffler on non-cat vehicles)
The lambda sond is on the pipe before the cat, not on the manifold.

i've not been able to find any reference on the parts catalog, could you tell me what part number is your 'not-cat' center tube?

thanks in advance

regards
zp

James Granger · Alfa 33 Joined: 10 Apr 2003 Posts: 302

ZP,

We checked out the underside of our 33, but couldn't find any part number on the muffler or any of the tube sections. The car does not have a triangular section attached to the muffler, and this confirms that the car is not equipped with a Cat. Here is a picture of what I observed:

The exhaust layout is identical to that of the original carbed Alfa 33. By the way, what is the engine code of your 1.3 IE, is it 30753 or 30755?

ZeNiTh-PbArM · Posted: Thu Jun 05, 2003 7:04 am Post subject: re : catalyst or muffler

hi!

i've been checking, my 33 is type 907a3b, engine 30753.
here's what the exhaust looks like :

http://alfaimola.free.fr/technique/echappement/echappement.png

so, i'm very interested in the fact that i could probably fit a "normal" muffler, provided that i change the manifold too.

if you don't happen to see any part number on the muffler, could you tell me what serial number your car is, that way i'll be able to check through the alfa parts cdrom what exact type of muffler you have, and i'll check the price too...it would be a great help!

thanks in advance,
best regards,
zp[/img]

James Granger · Alfa 33 Joined: 10 Apr 2003 Posts: 302

I made a mistake on the drawing - the manifolds are different, and more like the ones on your illustratation!

The serial number: ZAR907000*05870426

According to an Alfa repair manual that I have, the 1351 cc engines with Cat have code 30755, whereas the non-Cat 1351 cc engines have 30753 as their code.

Hope this helps

ZeNiTh-PbArM · Posted: Thu Jun 05, 2003 9:55 pm Post subject: re : cat & manifold

hi!

i've been looking in the parts cdrom, the drawings are not accurate, however your car is supposed to be fitted with the same cat as mine (same part number...and price too!)

on your car, how is the junction between manifold and center section? bolted with 3 screws?
and the center section, is it triangular-shaped or is the muffler round?

i'm trying to understand what's going on Wink

thanks once again,
regards
zp

James Granger · Alfa 33 Joined: 10 Apr 2003 Posts: 302

This is very interesting - maybe our car has a Cat after all, although I still have my doubts. Are you sure that your car has a Cat, is it not possible that what you think is a Cat is actually a Muffler?? Often, catalytic converters really smell of egg, our exhaust smells delicious!! I checked the underside:

The connection is by two triangular plates bolted together with 3 bolts, the connection is just before the 'hook' which holds the system up. The muffler is round in shape, and has a indentation running around it towards the front of the part.

ZeNiTh-PbArM · Posted: Fri Jun 06, 2003 5:49 am Post subject: re : catalyst

hi!

now, i'm sure your car has a catalyst! i have exacly the same one on mine.
when the cat is in good shape, no egg smell, that's normal.
besides, if you want to be sure, go to the local alfa dealer and ask how much it would cost for a replacement part : it's around 600 euros ; if yes, you can twice be sure it's a catalytic converter, since a normal muffler should be around 100 euros.

regards,
zp

James Granger · Alfa 33 Joined: 10 Apr 2003 Posts: 302

ZP,

I agree that we probably have the same exhaust system, yet there are still a few reasons why I don't think the car is fitted with a Cat. First of all, the engine codes: 30753, and 30755 are the same engines, except that the former is not fitted with a cat. The 30753 engine was fitted to cars which did not have to pass the U9/E2 emmisions test. This is the same with the 1.5 (30750 no cat, 30751 with cat), 1.7 8v (30736 n.c, 30737 w.c), and 1.7 16v (30746 n.c, and 30747 w.c). The engines without Cats also have less fuel system pipes (no fuel vapour sucking system) - I checked under the bonnet and these pipes are not present. The price you mention is ridiculous - you could buy a new 33 for that! I have also had similar experiences with high prices, for example a rubber air induction box hose for over 60 euros, eventually I went to the local DIY shop and found a suitable part for 2 euros. Maybe you could source a second hand part. There is a complete exhaust system for sale for a 16v with cat for 75 euro's (see link below), this gives an indication to the price.

http://www.marktplaats.nl/markt/autodiversen/ondalfaromeo/8163.htm?zoek=katalysator