Perplexed as to why this gap in Exhaust Manifold?

[mario]

So I started up my new to me 280 SL this morning to finally take it on its proper maiden drive.  Once I had her running for a bit, I noticed I had an exhaust smoke from the engine bay.  This is what I discovered.  Not sure why this wasn't mated properly on it's last visit to the shop.  Looking through my records now to try and determine the last time this was touched.  Can't tell if I'm missing the gasket either. 

I wonder if I get in there and tighten if the issue will be corrected.  May try that this evening. 

[Cees Klumper]

If there is a big gap then it seems clear it was improperly installed. I think (from memory) there should be a round copper gasket in there. Others with better knowledge please chime in.

[Jonny B]

A word of warning, be careful doing the tightening!! The exhaust manifolds are cast iron, and they are breakable. Look for overall fit issues to see if there is a binding, broken clamp, etc. Once broken they are just about impossible to repair.

[280SE Guy]

The gap looks correct. There is a metalic aluminum colored gasket/spacer that takes up the gap between the exhaust manifold and exhaust pipe. The nuts should be copper and can be obtained from your local Mercedes dealer along with the gasket at a resonable cost. The replacement of the gasket is best done on a hoist as braking the exhaust pipe from the manifold can be a chore if it has not been done recently.

Are you sure it was exhaust smoke and not some oil smoking.

As Johnny B mentions, take care with the tightening of the nuts.

Good luck,

280SE Guy

[Rolf-Dieter ✝︎]

At first when I saw the photo I thought it might be a flexatalic type gasket that provides a positive seal once compressed using the right bolt torque. Then I got to thinking since it is not a tight pressure seal like in a pressure line like a steam line this cannot be. Once I googled "Exhaust Manifold Gasket for 280SL" I came across the site below that shows a manifold gasket for a 280SL having a 0.8 mm (0.03") thickness. So I assume there is either a raised face or a spacer in the setup as shown in the photograph.

I recommend if one needs to know for sure one should order the gasket and have the gasket changed. While the work is done one can find out if there is a spacer or if it is a raised face on the flange / contact area.

This site shows the gasket ----> http://www.rockauto.com/catalog/raframecatalog.php?carcode=3018249&parttype=5400

As mentioned before tightening (specified torque value) would be important as is cleanliness and alignment (equal fastening of the bolts). If I had this concern I would let Mr. Muffler do this job providing him with the new gasket. The only question would be is it a spacer or a raised face. To be sure I would order 2 gaskets since a spacer would need a gasket on each side.

Perhaps someone that has done the job can let you know if there is a spacer or if it is a raised face flange arrangement.

[mario]

Thank you very much for the replies. I think I'll leave this one to the professionals. I'm going to go ahead and order the correct gaskets and bolts from my local dealer. Thanks

[Tom Colitt]

There are just simple 3mm thickness, round aluminum sealing rings inside those triangular flanges. One for each exhaust manifold to down pipe joint. Best to do both since they both have to come out of their "sockets" at the same time to lower the exhaust pipes. After tightening and crushing the sealing rings, the gap between the steel flanges should look about like it does in your picture and uniform all around. Using new screws and the correct, original type copper coated steel nuts is a good idea. All of these parts are available easily from most sources for imported car parts.

Regards, Tom Colitt
ClassicAutosLA

[jameshoward]

Having done this jobs twice recently (the second time because I tightened up the pipe improperly and broke the casting; very expensive mistake), your set up looks fine.