DIY Cat fitting?

[Chris1.4RT]

My standard cat needs to come off and be replaced.

I have a second hand cat to put on (I won't go into why I didn't go de-cat/sports/new etc).

Is it basically a case of unscrewing the four bolts, unscrewing the two lambda sensors and removing?

Then, refitting the new one?

I'm expecting to have to fit new bolts. Any particular size and sort I should be going for?

Is it worth cleaning the lambda sensors? If so what with?

Am I right in thinking I put paste on the cat pipe where it joins the centre pipe but not the manifold?

How does that work? Does it just plug into the manifold neatly and snug?

Also, how am I going to get under the car? Is it ok to use two trolley jacks at once and or axle stands? Where do I position the axle stands?

Lol sorry for sooo many questions but it's all greatly appreciated.

Cheers.

 

[Chris1.4RT]

OK I've found out the jacking points etc but if someone could answer my Q's about the actual fitting of the cat, it'd be great.

Cheers.

 

[Chris_H]

undo the bolts as you say. New bolts may not be needed, some seem to stay in good condition others rust terribly.

Clean the lambdas with a blowtorch, watch as they will flake off the hard carbon on the shroud.

yes paste the back half. Your not meant to paste the front as the paste can go into the cat cell and bugger it up, if you go easy and use a tuiny bit you should be fine.

yeah trolley jacks axle stands if your a fatty send a skinny under.

 

[Chris1.4RT]

Is the lambda cleaning really neccessary? I don't want to break them, besides, I don't have a blow torch.

Cheers.

 

[Chris_H]

not really needed tbh. When you fit it just tyake it a longish motorway run that'll clear them out a bit.

 

[Chris1.4RT]

Cheers Chris.

Does anyone know what size bolts I need?

I don't want to take to bits only to find I can't get it back on.

Wouldn't mind getting some bolts ready.

Thanks again.

 

[Fred@BTM]

which bolts are you on about? manifold to cat pipe? or cat pipe to centre section?

 

[Chris1.4RT]

Sorry yeah the manifold to cat. I noticed they have springs on them. Is that to allow some give and take but to keep it together snug?

I'm starting to think at £30 (they quoted) it'd be easier for my back street garage to fit it.

 

[Fred@BTM]

new bolt kit is about £10-£12 buy a new one just incase!

 

[Nigel]

It isn't a difficult job, but it is fiddley. The toughest bit for me was trying to stop the head of the bolt on the manifold side of the joint from turning. If you've got small hands you'll prob be better. I'm not a mechanic and I managed it ok!

 

[Chris1.4RT]

I might give it a go. I'll soak the bolts in WD-40 first for a day or two. I'm off work all this coming week.

If it looks like I'm going to have bother, I'll hand it over to the garage.

So the lambda sensors unscrew ok too? Do I need to be careful not to get WD-40 on them or is it ok?

Cheers dudes.

 

[Chris1.4RT]

20,000 post Yozza! COngrats!

 

[Fred@BTM]

JESUS f**king CHRIST!!! i need to get a life!