306 exhaust help please

[smoker]

My 1998 306 d (xud engine, non turbo) has just got louder and on inspection there is a split half way round a section of the exhaust. Simple and cheap enough, I thought, but...

Thre is a rear silencer, right at the back - that's fine. There's a centre silencer about in the middle of the car - that's fine too. The split is on a section of pipe which I now fear has a catalytic converter on it - just behind the cat (if that's what it is). Question - is this really a catalytic converter (on an xud idi engine)? And if so, do I have to replace it with another cat, or could I just a (cheaper) straight pipe connecting the manifold to the centre silencer. Would this pass an MOT? This is somewhat urgent so all replies welcome especially from anyione who has done just this.

Many thanks

[citronut]

hi and welcome

below is a link to BOSALS on line catalouge pug 306 pages seach to see which system is on you car then check for a straight through pipe to replace what you have,
if you do have a CAT in your system that is

http://www.catalogue.bosal.com/pages/ex ... &model=306" onclick="window.open(this.href);return false;

i d/cated my 98 1.9td XANT what a diference in gained get up and go

regards malcolm

[smoker]

Malcolm,
Many thanks for the quick reply. The catalogue you linked to does indeed show a Cat – confirms my suspicion. Further research has shown (as far as I can tell) that a diesel MOT for this vehicle only involves a smoke density test. Does a catalyst make a difference to this (or does it simply reduce other emissions which are not tested). In other words, am I right in thinking I will still pass without a cat?

Very tempted to try a straight pipe – think of the weight saving and power gain!

[Oldpug]

I have an old 95 non turbo 1.9 and it has just a straight pipe? Yours is not a "catalyst" as in all the late stuff as there is no electronics to back it up,its just a sort of particulate filter.They will run OK and pass the MOT with out them,so you can just fit a straight pipe.

[smoker]

Many thanks for the reassurance, oldpug. I’ve ordered a straight pipe and will try and fit it later this week. Fingers crossed. I might see about getting the old part welded for use as a temporary spare should I ever need it.

[spider]

As above no need for cat although some did have them fitted when new.

Note: Later 306 XUD's (non turbo) units have the exhaust manifold offset slightly so you cannot easily fit the earlier pipe to it. If I remember they are a bit of a pig of a job to get the exhaust nuts / spring up on the later ones given the tight space.

[citronut]

if it had/has a cat and you remove it this will not affect the emmisions for the MOT on diesels of this age,

as i said i have a 1.9TD XANT which i de/catted a couple of years or so ago and has not been any problem at MOT time,

regards malcolm

[smoker]

OK - job done! £33 for the pipe and fittings from Unipart. Fiited perfectly (i.e. the pipe was the right size and shape). BUT - what a pig of a job!

Access to the two "spring loaded" 10mm bolts which join onto the manifold above the damper is a nightmare. I had to hacksaw them off from under the car and really struggled to refit the new ones. The design of the bolts looks like they could be assembed on the pipe and slotted into place but this would need a special tool to compress the springs - is there such a thing? Handy to know for future reference.

[spider]

No there's no tool for it. A long selection of "wobbly" extension bars is normally used along with someone to hold the bolt in place while you compress it slightly to get the nut to fit initially. You normally only fit the bolts then hold the rest of the bits in one hand, tool in the other and a third hand ( ! ) to hold the bolt head down.

I did say it was a pig of a job on those , earlier shape 306 XUD / both shapes XUDT and DW8 are easier.

[smoker]

Oh well - thanks anyway. I think the part that failed was original - 108k miles. If this bit lasts as long that could be another 6-7 years or so before it's due again!

Thanks for the support.