Info please from anyone who has changed or cleaned a DPF

[horsedentist]

Hi
I have a new particle filter on order for my wife's C5 Looking at the old one today the 4 bolts that hold the two parts together look as though no matter much wd 40 I put on them they will shear off when I try and undo them. Are they bolts or studs?
I was hoping to split the filter in situ as the front clamp is damn difficult to get at but if they are studs I suppose I will have to take the whole thing off to drill them out.

[horsedentist]

Anyone know if they are captive bolts or screw in studs? Looked on the internet to no avail plenty of Peugeot ones which are clearly ordinary nuts and bolts.

[RichardW]

Which engine is it?

OK - see from other thread it's an early Mk1 2.2 - which case service.citroen shows studs screwed into the front part with nuts on the back. Later cars used through bolts. Should be able to cut the nuts off, pull the back part off, then attack the studs with heat / plus gas / stud extractors etc to get the studs out. probably drillable in place if it comes to it.

[civvie]

Yes they are studs, I took mine off and cleaned it, three nuts came off fairly easy after a good dose of plus gas, one was solid but with careful use of an angle grinder on the nut I managed to get the nut off.

[horsedentist]

Cheers thanks for that might have helped if I had posted the technical details senior moment.
I wasn't sure if they were studs or captive bolts as it is so rusty its hard to tell.
I think I can get them off ok as they look so corroded I think they will shear off flush lol I will try them tomorrow with an impact wrench see if there is any hope of them shifting but not too optimistic.

[civvie]

If you can I would suggest getting some plasticine mould it around the nuts and fill with plusgas (not WD40) and leave it overnight, might give you a fighting change then.

[horsedentist]

Thanks I will try that I have some of the good old fashioned releasing agent I can remember when it came in a can with spout like an oil can no aerosols in those days lol

[HaydnR]

The top two on mine came out easy but the bottom ones sheared, had to drill them out which was a pain. To remove the contents of the fap I used an sds hammer drill and a 18" 20mm masonry bit.

[horsedentist]

RESULT! top two came undone bottom two,one sheared off and the other I can't do anything with, it is so rotten it just crumbled away and now resembles a cone shape. So I will cut the little devil off with the grinder in the morning. So only two holes to drill and both easy to get at. Still no sign of the new blooming filter though! Could be some recycling called for me thinks.

[horsedentist]

Update

Got it off and was blocked absolutely solid couldn't even blow compressed air through it. No wonder it was throwing fault codes and going into limp mode now and again it was a wonder it ran at all!