It seems odd that a leak there would cause black smoke. I wonder if you don't have an obstruction further down the exhaust system that increased the exhaust pressure causing it to find the weakest spot to start leaking.

This topic would probably get a better response in Diesel Discussion.

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Whoever said there's nothing more expensive than a cheap Mercedes never had a cheap Jaguar.

83 300D Turbo with manual conversion, early W126 vented front rotors and H4 headlights 400,xxx miles
08 Suzuki GSX-R600 M4 Slip-on 22,xxx miles
88 Jaguar XJS V12 94,xxx miles. Work in progress.