CAT Replace

[PepperRed04]

Hi all,

I have a 2004 Tddi & was wondering if the CAT is easy enough to do on the drive, or does it need ramp access ?
If ok to do at home, anything major to look out for ?

Thanks in advance,

[metalworker0]

These bolts/nuts unlike any other bolt on the van are going to be seized solid, welded by cycles of the exhaust heating and cooling , they often need oxyacetylene to loosen them up, just think they may have been on there for nearly twenty years and have never been undone, they will often snap off and cause more work.

Don't think you'll get at them without jacking the van up and putting it on axle stands, you'll need long extensions on your ratchet ..perhaps two long extensions making up a length of of two foot or more.

That's all a worse case ..a good case would be that the catalyst has been taken off in the past perhaps less than two years ago if major engine work has been carried out.

ask your local tyre and exhaust centre how much to take it off ......any less than £40 and it will be worth every penny and you'll be saving yourself a whole load of bother.


all the best.mark

[PepperRed04]

Thank you for the detailed reply Mark,

Looks like then it'll be best wait until I get the clutch done in a couple months !

[metalworker0]

I was wrong about the ratchet extensions , just had a good look ....was having exhaust hanger rubbers replaced after advisories on MOT. so it went on the ramp at my local tyre place.

£15 for 3 hangers and fitting total ....so some jobs just not worth bothering about doing myself, took 20 minutes. would have taken the entire afternoon if id have done it myself, and would have been hard work as well. jacking it up ..axle stands, struggling ..lying on the floor .

Anyway ....
The cat comes undone from the top, there are bolts pointing down ..the EGR cooler may be in the way to get at these. so that may have to come out

You may have to undo rear engine mount to lean engine forward to do the job with better access .

If bolts have been trouble in the past and stripped the threads..there may be nuts on the bolts ...then you'll need the ratchet extensions.

Note: MY ANSWER - All this is speculative, and guess work ...as I've not done this job on my van ..just observations from looking at it.

All the best.mark

[metalworker0]

This video is helpful

https://www.youtube.com/watch?v=WNoh9l2_74g

also i said bolts above ..i meant nuts..there are studs going into the cat flange ..with nuts holding it to the turbo

all of them look vary hard to get at .

Here's a picture of the back of an engine ..you can see some of it ..but a lot of it is hidden ..even with the engine out , so you've got a job on.

should have checked my cat ..but didn't ..and i've noticed when i give mine maximum acceleration up a steep hill ..i can here exhaust gasses escaping ..so this summer I may be in the same situation as the video guy

all the best,.mark

[Kenton]

Just to add my tuppence. I fitted a de-cat pipe on my van, which was the first time I had to look at the CAT connection to the turbo, and it came apart quite easily to be fair. Soaked in penetrative spray for half hour first to make sure, then a semi-long extension to reach the four bolts, and CAT came off. Nothing got in the way. The turbo connection to the other ancillaries were done from the top. I have since then replaced the turbo, and the rest of the exhaust. All is easily accessible. Just depends largely on where you live, as to whether the atmosphere is salty, as that can impact the hard steel greatly, and cause seizures on bolts etc. If not greatly affected, it SHOULD be ok. Not a driveway job in my opinion. Ramps are the way. You can find places these days that rent out ramp time. Worth a look, unless you know someone with a garage.
Good luck pal, let us know how you get on.

[PepperRed04]

A belated thank you for the additional info - kinda put it to the back burner for a while whilst I try & get my other project ( Dolomite 1300) road ready for summer.

Had a quick look tho & the bolts/fixings from the top "look" to have pretty clean threads so will give it a bash on axle stands at some point over the coming weeks.

Thanks again,