How do I reconnect flex pipe to down pipe? - PeachParts Mercedes-Benz Forum

shertex · #1 10-10-2015, 01:19 PM

This is on my 91 300D. Between the pipe that comes from the turbo and the down pipe there is a flexible section that's about 10" long. On the turbo side, it looks like it fits inside the pipe and appears to be secure. But on the other end it has become detached from the pipe. The two ends are touching each other but they are off center so that exhaust gas escapes through a 1/4" opening.

How do I go about securing that? Or is it something I have to replace? If I were to guess, the part of the flex pipe that's in the down pipe has broken. Can the flex pipe be lengthened? Also, I'm having trouble finding it in the EPC.

I am open to both correct solutions and "ghetto" solutions.

Thanks.

sixto · #2 10-10-2015, 02:19 PM

Something like this might do it albeit reducing flexibility -

I'm dealing with the same thing in the SD except the pipe came clear apart. One option is to have a generic flex section welded in place.

Sixto
83 300SD

Diesel911 · #3 10-11-2015, 10:33 AM

Quote:

Originally Posted by sixto

Something like this might do it albeit reducing flexibility -

I'm dealing with the same thing in the SD except the pipe came clear apart. One option is to have a generic flex section welded in place.

Sixto
83 300SD

I have used this type of clamp before and in the face of a lot of vibration the clamps will eventually fail in part because the metal stretches stretches and is thin.
In order for the above pic to last the 2 sections of pipe would need a section of tube that slides in and fits the inside diameter so that the Pipe remains centered to each other and all the clamp has to do is keep the 2 pipes from sliding in and out and seal.

vstech · #4 10-10-2015, 02:28 PM

two options...

cut out the broken flex, and weld in a replacement flex section. hard to find it in the correct size though.

the other option is order a replacement flex section from our site, or the dealer...

shertex · #5 10-10-2015, 03:00 PM

Sounds like my best bet is to order a new flex pipe from MB.

Sixto, I am glad to see you are no longer MB-less.

shertex · #6 10-10-2015, 03:01 PM

So how does the flex pipe connect to the solid pipe? Some sort of sealant?

shertex · #7 10-10-2015, 03:06 PM

I wondered about using Tiger Patch as a stop gap measure...but maybe that's a bad idea.

Dan Stokes · #8 10-10-2015, 04:58 PM

I had a heck of a time getting mine back together on my 617 (I'm guessing it's similar) but I fiddled and it did eventually slide together. I did tap the one end a tad bigger by working it carefully with a hammer from the inside. Once it was on there the clamp secures it very well. I'll wager that a new one will fit better.

The flex section on the 617 is really short - maybe 3 or 4 inches. Given that yours is about 6" I'd think you could get a replacement generic flex section though I'll confess that I've never gone looking for one. The one in my exhaust pipe (goes thru the front fender) is about 6" but it has a short section of solid pipe at each end so the total length is probably 8" or so. There's a pic in my build thread if you want to dig for it (no clue how to do a search for that).

Dan

vstech · #9 10-12-2015, 01:28 PM

4 hours

shertex · #10 03-19-2016, 09:37 AM

Five months later and my patch is still intact. Keep waiting for it to break so I am motivated to get it repaired the right way.

vstech · #11 03-19-2016, 11:25 AM

Did you take any pics of the patch?

shertex · #12 03-19-2016, 11:39 AM

Quote:

Originally Posted by vstech

Did you take any pics of the patch?

No....I'll see if I can take one since I still have the encapsulation panels removed. But to describe it....it's a very generous wrapping of Tiger Patch, and then the heat resistant tape wrapped over that. I've checked it at least once a month and it seems to be holding fine. As I may have mentioned, my particular issue is that the bottom of the flex pipe broke such that it was about 1/4" off center from the down pipe. My guess is that, once that stress was relieved, it doesn't want to break any further....and the tape is flexible enough to absorb the inevitable vibrations.

shertex · #13 03-19-2016, 01:51 PM

Here's a pic… That section of pipe is badly rusted so I will just replace everything when I replace the pipe.

Everything after that section of pipe was replaced by the PO around 2007....looks practically new.

yuke · #14 03-19-2016, 05:15 PM

Glad the ghetto fix worked shertex as long as it do'nt leak is what counts. Those flex pipes seem to always be the weak link in the chain.