Jettisoning silencer at 70mph

[dieseldave]

So there I was happy as Larry heading down the m4 at 70mph when there was a scraping noise followed by a bang. I looked in the rear view mirror to see my silencer skating down the road and then bouncing end over end just before disappearing under the wheels of an artic. Luckily no one was hurt and miraculously the truck was undamaged.

I pulled over on the hard shoulder and froggered my way out into the road to grab what was left of my mangled exhaust.

Long and short of it is I now have a very agricultural sounding van with no silencer. Turns out what had happened was the O/S exhaust mount between the chassis and the silencer had suffered metal fatigue and snapped through leaving the exhaust supported only by the compression clamp holding it to the downpipe on the N/S end this obviously rattled free and let go neatly jettisoning the silencer.

Now the thing is what I'm trying to find out is how the silencer is actually MEANT to be held in place. On my bus the silencer O/S end had a bracket welded to it that was then fixed to the chassis with the N/S end only supported by being clamped to the downpipe and located in a semicircular bracket... on reflection this doesn't look right as I can see how the bracket was exposed to a bending moment everytime the engine moved a bit (or should this have been absorbed by the downpipe?)

All the silencers (new and 2nd hand) that I've seen for sale seem to not have any brackets welded to them, and not being a welder myself yet (start my C&G course in Jan!) can't work out how to fit exhaust.

It seems to me unlikely that all exhausts are welded into place so can anyone shed some light on how the silencer should be mounted, Is there a set of brackets available that clamp the silencer in place? and how can i ensure that any bracket holding the silencer on doesn't suffer fatigue in the same way?

All help, suggestions, advice, and flames gratefully accepted!

Dave

[kevtherev]

Dave
Having looked at Vagcat exhaust diagrams I can confirm there are two muffler mounts for the JX 1.6 D
Both mounts are welded to the muffler, then there are various plates and bonded rubber blocks attached to them
There is also a version of muffler with bolted on mounts.. Part No 068 251 053J

[Oldiebut goodie]

The silencer shouldn't be fixed to the chassis - the mount will work harden and break due to the movement between engine and chassis. They are fixed to the engine with the two brackets. Sounds like someone did a big bodge job there.

[kevtherev]

Bodge up indeed..

[weldore]

if its anything like the 1.6 diesel then the silencer has 2 brackets welded to it either end and the o/s bracket has a rubber mount bolted to it and off that mount another bracket that runs down to the sump.these brackets tend to snap midway