Even if it looks like there are no bent valves I would still check them. They sit perpendicular to the cylinder bore, not offset like most engines, so even if they've been tagged by the piston they don't bend to the degree they would in other engines. All it takes is a few thou to cause a leak. Clean the head around the valves, set the head so the ports are facing up & pour some liquid (water, alcohol, gasoline) in the ports & look for seepage at the valve seats. Now's the time to address it if they leak.

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82 300SD 202K
82 300SD 233K
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82 300TD 98k euro (parts on the hoof)
85 300TD 282K
83 300TD 197K