hi guys

my catalyst converter has 2 big holes and the mot is coming up very quickly. how hard is the job the rest of the exhaust system looks ok just a bit rusty. it looks quite simple to unbolt its just separating the cat from the back box how its slid inside the back box is their any special way of getting it out or is it just a job for the lump hammer & steel chisle?

any feed back would be great guys

Rust is your enemy. Probably you'll land up requiring new nuts & bolts & clamp.A source of heat would be beneficial. Safety first when working under the car.

i have some ramps and some bricks for the wheels once it is on the ramps i feel safe enough =/ but ur making me doubt it now lol it seemed sturdy enough when i had it up to see where the hole was

In the process of doing the same on my MK2. Make sure you've got replacement bolts as I've had both of the bottom ones connecting to the center pipe break on me.

Also it's worth while running the engine for 10 minutes before attempting to remove the 11 bolts holding the cat to the car (may be more or less on the MK1), the sensors might be difficult to remove too so take it easy until you feel the rust seal break.

Depending on where the holes are, it may be possible to get them welded up.

bujking said:

hi guys

my catalyst converter has 2 big holes and the mot is coming up very quickly. how hard is the job the rest of the exhaust system looks ok just a bit rusty. it looks quite simple to unbolt its just separating the cat from the back box how its slid inside the back box is their any special way of getting it out or is it just a job for the lump hammer & steel chisle?

any feed back would be great guys

Click to expand...

are you sure its your cat and not middle box? should be cat, middle box then back box

dave said:

are you sure its your cat and not middle box? should be cat, middle box then back box

Click to expand...

As far as i can see it goes manifold flexy pipe cat then back box I think on the later models the cat is part of the down pipe or manifold

wd40 soaking

Any stubborn looking bolts - well infact all bolts should be blasted with several rounds of generous amounts of WD40 or any pentating fluid to be honest

The Studs will probably come out with the nuts.... so you will need ones most likely

New Gaskets

Radiator Fan might be removed for better access.... but be carefull of the exposed radiator

And The Cat might be easier to drop down....

Oh and its VERY HEAVY

Not a hard thing todo tho

Ziggy

bujking said:

As far as i can see it goes manifold flexy pipe cat then back box I think on the later models the cat is part of the down pipe or manifold

Click to expand...

The Cat as part of the Manifold is refered to as a Mani-cat (manifold Catalyst)

Should go Mani Cat - flexi with a middle box or pipe - Rear box

Lamba sensor change over might be a bugger tho

Ziggy

Ziggy122 said:

Should go Mani Cat - flexi with a middle box or pipe - Rear box

Click to expand...

op has a mk1 no fannycat

dave said:

op has a mk1 no fannycat

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I'll see if I can get some pics up just not sure if I can upload them with a phone.thanks for all your help

So what would be the best way of seperating it from the backbox? Brute force

big hammer

With a car lift and proper tools its an easy job, so for what the labour costs it would be well worth using a garage. Grovelling on the floor with lead lamp and DIY tools its a barsteward to do.

Lambda will probably get fubar pulling it out.

Run the engine to heat the studs then squirt with plumber's pipe freeze spray to thermal shock the nuts. Angle grinder might help but use some wrap-around goggles sparks fly everywhere under a car.

Ramps are not good its all to easy to drive the car off the front end and one often skids forwards when you try to drive up.

A trolley jack and decent axle stands are easier and hardly any more expense. Always chock the back wheels when jacking the front.

WhiteSei said:

Ramps are not good its all to easy to drive the car off the front end and one often skids forwards when you try to drive up.

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Easy way to prevent them skidding is to tie some rope to the front rungs. The car runs over the (loose) rope, which holds them in place. You're then free to drive right over them!

Mk1 cat has no lambda attached to it. The cat comes after the flexi. Very easy job, but as I said earlier rust will be the main problem. New nuts&bolts, plus exhaust brackets. Actually if you can get a grinder near, grind them off simple.

guys thanks again for all your help ill have to dust off the axle stands i dont have a angle grinder put in sure i could sort some thing out i was thinking take the cat and back box off first so im not under the car when i seperate them

from memory it is 2 bolts 2 u brackets and one gasget i will need ill have a look at the weekend as its always dark when i get home from work

It's unlikely to fall off axle stands, but if you can, put something (old wheels with tyres on are good) underneath the car so it can't fall off and crush you.

Totally off topic & the wrong time of year, but I remember a long time ago......Underneath a mk2 xr2 changing zorst, jack, axle stands all fine. Wrong...hot day, stands sinking into the tar, me panicking, wife came out with coffee, just in time to pump up the jack...whew

My point is you can't be too careful.

Yep. Good idea to have a watcher/tool passer.