I had the same with my 200tdi. It was running on it's own oil.
I'd just clean all the pipes out & start driving it again.........till the TD blows up that is.
I've got for sale a wide angle rear prop of a 2.5/2.5TD/200tdi Defender.
Can't remember what make it is but it's not a sh*tpart.
Can post pic's but not till the weekend.
Looking for £80 + carriage