This spring, after getting the normal check out (dwell, brake fluid change and the like) the car was running quite nicely. I then took it to the office and it sounded like a freight train. Discovered an almost three inch long crack in the rear exhaust manifold.
After much fussing about trying to weld it closed (there was a weak spot in the casting, etc.) the machine shop got it done. Ted Gottfried, got it all back together, and when he went to tighten it down, got another crack. He had suspected that there was a mis-alignment problem from the welded exhaust system to the joint on the header, but thought there was enough give in the system, along with a thicker gasket to make it work.
This turned out to not be the case. So now, I have a used rear manifold (properly cleaned and painted with Eastwood high temp paint) in place. Ted was able to make enough of an adjustment in the exhaust pipe to make it work. We may need to make some further adjustments but for now it is fine.
He priced out a new one, but at close to $900 we decided to go for alternatives. Turns out that the exhaust manifold is common to most of the 129/130 engines (250, 280 fuelie cars). Obviously you need to double check the numbers, but at least there are other alternatives. Joe A. can probably speak more cogently on the fits from other MB models.
I wanted to pass along the learnings.
BTW, it ran fine for two years before it decided to let go with the crack. Have no idea why, as we had done no dis-assembly or work on these components.
Jonny B
1967 250SL Auto
