Technical Ducato 2004 2.8 jtd Crankshaft Oil seal

[digger8954]

Hi all, can anyone tell me if there are different crankshaft oil seals for this engine. I have sourced one from ebay and it didnt seem very tight around the shaft surface. The one on ebay seems to cover 2.8 models from 97 to 2006?
Also is it possible to change this seal with the engine still mounted in situ or is it an engine out job? I appreciate the timing belt etc will have to be removed.
I beleive the engine type is 8140.43 S or N

Thanks in advance. Mark