Plain Jane OEM nothing to see here rebuild

[JustJeff]

Originally Posted by RETed

It should have a similar mark on the turbo exhaust manifold.
Gasket looks okay...
Was the turbo exhaust manifold not bolted down tight enough?
Crack?


-Ted

We saw the same thing in that pic. Sometimes I post things to confirm what I'm already thinking, but also others can learn if they run into similar situations. A lot of times car forums have people posting the really cool and extreme stuff they are doing, but don't post mundane things. The mundane things I think help people such as myself, who don't have large real life network to bounce ideas/experiences off of.

That being said, Yes, IIRC I did have problems getting the front of the exhaust manifold bolted down. On the first rebuild, after the engine had been installed I then made the untimely decision to put new exhaust gaskets on. I do remember having trouble getting the front manifold nuts tightened down correctly. But also as this pic shows, I do have cracks in the manifold. They were there when the initial rebuild happened last year, I was hoping they were not long enough to cause a leak.


I have a spare S5 turbo manifold in storage, I'll get that either later tonight or tomorrow morning. I remember that the manifold wasn't in perfect shape, but that's as much as I remember.

What I don't know is what to expect from symptoms of an exhaust leak at that location. Louder exhaust, but what else?

I have heard of people welding and repairing cracks, but I've also heard that often times that the welded repair then becomes a problem down the road. It sounds like repairing those cracks are more a temporary fix than an long term solution. But the reason I'm bringing up temporary fixes is that this summer I will be taking welding classes. It is possible that this summer I will meet someone through the instructor of the class who could weld a new manifold for me. If I could learn to do the work myself that would be better, but might be a little ambitious of an expectation from an entry level welding class.

[RETed]

Originally Posted by JustJeff

That being said, Yes, IIRC I did have problems getting the front of the exhaust manifold bolted down. On the first rebuild, after the engine had been installed I then made the untimely decision to put new exhaust gaskets on. I do remember having trouble getting the front manifold nuts tightened down correctly. But also as this pic shows, I do have cracks in the manifold. They were there when the initial rebuild happened last year, I was hoping they were not long enough to cause a leak.

I have a spare S5 turbo manifold in storage, I'll get that either later tonight or tomorrow morning. I remember that the manifold wasn't in perfect shape, but that's as much as I remember.

What I don't know is what to expect from symptoms of an exhaust leak at that location. Louder exhaust, but what else?

It looks like this turbo exhaust manifold is just a door stop...



The red arrows goes to the two, obvious cracks.
Most of the time, you just worry about the cracks.
It looks like in your case, the entire area between the two cracks has shifted.
Encircled in red...
This would explain the soot marks on the gasket.

To fix this case, you'd need to first weld the cracks and then machine down the flange flat.
Unless you've got the resources to do this, it's way too much trouble.

Small exhaust leaks start out as ticking sounds...
As they get worst, they progress to a pfft...pfft...pfft and sometimes whistling sounds like old-school VW engines.

I have heard of people welding and repairing cracks, but I've also heard that often times that the welded repair then becomes a problem down the road. It sounds like repairing those cracks are more a temporary fix than an long term solution. But the reason I'm bringing up temporary fixes is that this summer I will be taking welding classes. It is possible that this summer I will meet someone through the instructor of the class who could weld a new manifold for me. If I could learn to do the work myself that would be better, but might be a little ambitious of an expectation from an entry level welding class.

Yeah, see above.
The consensus on these turbo exhaust manifolds is that you either got a good one or you don't.
Many of them warp - due to the metal content.
Some of them warp (and crack) to the point where they are junk.
It's usually easier and cheaper just to replace.


-Ted