Shhhhhhh a bit

[Jon K]

The rose nut came off OK. The front pipe, not unlike the rear one, is welded on though. So the entire exhaust is one piece which made it a bit of a challenge to get off!

Welded front tube:


It's off now, so I just need to work up the courage to take an angle grinder to it and hope there wasn't a very good reason why it was welded.

When you say the rear pipe should be bolted on, do you mean it inserts some way into the silencer and the the bolt passes right through both silencer and pipe to hold it in place? Won't that push the new baffle in too far for it to get a grip? Or does the 'fat' end of the baffle friction fit into the pipe, therefore protruding into the silencer, and the bolt go through all three?



Sorry for all the questions and my lack of knowledge.

Thanks Ian,

Jon

[IanCordes]

Just as well you didn't cut the manifold nut off! Now no way of getting a new one on. Here is a couple of pics of an original exhaust. It has the curved tailpipe, which from the fixing hole, you will see goes quite a way into the silencer. The perforated baffle tube is just pushed into it. Is this original? I can't be sure; others may know; but it fits. In the second picture there is a baffle tube from either a roadster or an earlier trials Villiers silencer, by way of illustration. A cut-down and swaged down version could be pressed into service in the same way as the perforated tube in mine is. My one was very loud; but not as loud as without it! Now you at least know more or less how it should be. I have two twin cylinder (3T) engined machines, both have the standard version of that silncer, and they are not loud.

[Jon K]

Evenin all,

As advised, I’ve cut the end pipe off the silencer. Problem is, now I’ve found a metal tube across the inside of the silencer through which the bolt passes. So there’s no way I’m getting a baffle in there unless I cut that tube out somehow. And, the outer diameter of the end pipe is greater than the inner diameter of the silencer. So what do I do now?



Jon

[IanCordes]

First of all Jon, to be clear, nobody advised you to do anything! I showed you how it should be. In post #11 on this thread I said 'You now have to make the decision.....', finishing up with:- Your call.....'!

What is evident in your photo is a double thickness of metal, which means some of the tailpipe is still inside the silencer. This is how thin the metal from which the silencer is made actually is:- Someone has seriously messed with your exhaust system, mistakenly thinking they could improve on the original, no doubt. If that remaining tailpipe comes out, along with the spacer, you will then be able to insert the tailpipe, and a baffle.....

[Jon K]

Oh blimey sorry, I didn't mean to imply blame - I was just saying I think I'd done as 'suggested', that's a good thing. Frankly I'm glad to have got as far as I have and I thank you for giving me the information and confidence to do it.

And, Ah - that makes sense. Thanks again.

[IanCordes]

No worries, Jon, but one does have to be careful about giving advice on these forums (fora?), and do it with a caveat that it is the responsibility of the recipient of such advice to ultimately decide what needs to be done; as you have.

I did mention in that same post that there may be a bit of the tailpipe left in there after cutting the main part off:- 'You now have to make the decision as to whether you carefully cut the pipe off where it joins the silencer, without touching the silencer. Once done, hopefully the remaining pipe still in the silencer will come out with gentle persuasion.'

Enlarging your photo, one can clearly see the 2 different tubes, one inside the other. I suggest that the spacer is part of the remains of the tailpipe, which logically will only be retained now by a thin bead of weld around the perimeter. It may be possibe to grind that away, grinding from the inside at an angle perhaps, with a small grinding wheel? It may in fact be free, only held in place by age and carbon. In which case, a firm grip of the spacer will give you some purchase to get it out. Once free, out should come the unwanted tube complete with spacer.

I have just checked, and a baffle tube from a full-length silencer would then go into the silencer completely, and could be retained by a small nut and bolt, which would do the job. However, as it is the same diameter as the tailpipe, it would not allow the tailpipe to be fitted. Not ideal, as the gasses would blow directly onto the rear subframe tubing, as well as being close to your leg. However, cutting a baffle tube down, cutting slots in one end in order to swage it down so that it can be jammed in the tailpipe should work? Thus, the tailpipe needs to be in the silencer a reasonable distance, imo.

If you can find a cheap, cosmetically challenged silencer, it could donate its baffle for the project.

[Jon K]

Cheers Ian, I’ll have a go at it with a grinding cone thingy, ordered just now..



and if that doesn’t work I might have to try a metal blade in my multi tool.

If all goes well, I’m still hoping to be able to get a baffle of some description that’s narrow enough to ‘reverse fit’ into the tail pipe. I doubt I’ll find an old silencer, Even one that’s rubbish enough to be a donor.

Wish me luck. I’ll let you know how I get on.

Jon

[IanCordes]

You may be able to get good purchase on that spacer tube, to try and turn the remains of the tailpipe in order to break it free. A bit of heat may help if it is stubborn, or try giving the tube a hard whack, inwards initially, to see if that breaks it free.

It is worth putting a 'Wanted' post under 'For Sale and Wanted'. You never know what members here have tucked away, lurking under a bench or on a top shelf! I have a rough silencer with baffles, but a better silencer with no baffle, and with several projects on the go I can't part with anything until I can be sure I won't need them. I have parted with something recently to a member, only to find I had miscalculated, and actually needed it myself! Too late....

Good luck with it. I think you can see the wood from the trees now, although there is not much you can do about the downpipe being welded to the main exhaust. Careful with those threads on the manifold nut, as you won't get it off to change it!

[Jon K]

Thanks Ian,

I may have another problem. I remembered I had a cheap endoscope stashed away so I had a look inside the silencer. It appears there is a baffle in there already, unless that's just what the inside of a silencer looks like.



I suppose I'll press ahead. Hopefully, if it is a baffle it'll come out with the remaining tailpipe.

[IanCordes]

I can't really make that out, Jon, but it maybe. There is a baffle plate about 1/2 way down the silencer, attached to the silencer itself, with a hole in the centre through which the baffle tube passes. I wouldn't recommend touching that. It will quieten things down a bit in conjunction with an effective baffle tube, as well as centralising the tube

[Jon K]

Excellent! Thanks Ian.