Weld exhaust joint?

frankh · #1 07-09-2008, 09:32 AM

Morning all,

I have a vettermen exhaust on a parallel valve IO360 and the slip joint in the pipe at the #1 cylinder (front right) is leaking. It looks like it was maybe over expanded a little when the pipes were formed and as a result I get a leak that is bad enough to stain the inside of the cowl so it probably needs to be deal with.

This particular joint is bolted together and therefore cannot move in theory, i.e it is not a slip joint that moves to take up expansion.

I have tried an exhaust bandage and that has not lasted long so i was thinking of pulling the pipe off at the next oil change and simply TIG welding the pipe together at the joint.

Can anyone see any reason not to do this??

Thanks

Frank

Bob Martin · #2 07-09-2008, 09:48 AM

Just ask Larry Vetterman about it.
He is very helpful about these kind of issues.
I had a leaking pipe in a slip-joint a few years ago.
After speaking to Larry about it, he had me send it back to him for adjusting!
He reworked all the joints and even shaped up the flanges where they attach to the cylinders and if I recall correctly, he even sent new gaskets.
and to top it all off.......it was no charge!! and this was a 5+ year old plane.
That is service!!

as a side note......at the time I was trying to cool engine temps down a bit and somehow thought that wraping the exhaust with an automotive heat resistant wrap would help. It didn't and probably caused the out of round
issue I had with the slip joint......Larry even asked if I'd wrapped the pipes with something as he could tell from looking at the pipes.....he cautioned about wrapping and explained how the extra heat cause the SS to move around, etc..........but even knowing I may have caused the problem, he still fixed it......
This is why I say call or email Larry, you will be going straight to the top.
Good Luck

N941WR · #3 07-09-2008, 03:50 PM

Frank,

You don't want to weld that slip joint together as the cylinders move ever so slightly and causes that thing to slip back and fourth.

This is the same reason baffles shouldn't be bolted to two cylinders at the same time.

frankh · #4 07-09-2008, 05:31 PM

that joint is bolted together with one of those tabs...I'm Confused..

AlexPeterson · #5 07-09-2008, 05:43 PM

Frank, are you talking about the joint that is essentially vertical? One reason to not weld it is that may not be able to remove the pipes (or get them back on) if you weld them. I'm not certain, but have a look or maybe someone with the stuff just sort of mounted temporarily on their engine can give it a try.

N941WR · #6 07-09-2008, 06:21 PM

Frank,

I'm sorry, I was thinking of the horizontal slip joint where the pipes cross over. You were specific, I just wasn't reading.

I do think your question was answered in the reply above.

AlexPeterson · #7 07-09-2008, 06:39 PM

Quote:

Originally Posted by N941WR

Frank,

You don't want to weld that slip joint together as the cylinders move ever so slightly and causes that thing to slip back and fourth.

This is the same reason baffles shouldn't be bolted to two cylinders at the same time.

BTW, I know the horizontal slip joint is not what is being discussed, but the "ever so slightly" relative movement is actually quite a bit - maybe 3/16"! Those pipes get a lot longer at 1000F plus.

Mel · #8 07-09-2008, 06:54 PM

Call Larry Vetterman at 605-745-5932. He will tell you what to do.

asav8tor · #9 07-09-2008, 07:04 PM

Welding will cause run away cracking. More welding to fix the cracking. More cracking. More welding. More cracking. More welding. More cracking.

Eventually you will end up buying a new set of pipes.

or

Just don't weld.

AlexPeterson · #10 07-09-2008, 07:27 PM

Quote:

Originally Posted by Mel

Call Larry Vetterman at 605-745-5932. He will tell you what to do.

Yep. I had the same thing, and Larry took care of mine by expanding the inner pipe until it fit nicely in the outer pipe. Fix it or it will just keep beating on itself and get worse. Call him.