Oil leak series 2 diesel

Hi,
I've got a 1968 series 2a Diesel and have recently changed the water pump, noticed oil leaking since from what looks like a bolt that holds the water pump the the timing plate. Is this normal ? Tried stopping it with some blue gasket sealant by taking bolt out and back in with sealant but leaking again !!!!
Any suggestions ?
It's the long bolt just above and left of pulley.

Cheers

you might want to try a different forum, i.e. https://www.landyzone.co.uk/forum/series-land-rovers.6/ or https://www.landyzone.co.uk/forum/common-faults-and-questions.38/