Smoking Disco

Hope someone can help:-
'94 300TDI Disco has been smoking(blueish) with a Diesely smell on overrun especially down steep hills and getting worse for the past 20K miles.
Turbo and injectors are new, EGR has been blanked off and Cat binned. Intercooler and inlet have been cleaned.
There is no back pressure at the filler cap or dipstick when either hot or cold. I've been told it may be the valve oil seals.
If so can they be replaced without taking the head off by bringing the Piston to TDC and compressing the spring.
Any advice welcome, MOT looms nearer

have you checked injector timimg as that can give symtoms described

Yeah as above... I had a similar blue smoke problem not long ago, bought a disco 300tdi that had just had its timing belt done and whoever did it had put the pulleys back on the wrong way round, swopped em back and problem was cured

uncle albert said:

have you checked injector timimg as that can give symtoms described

Click to expand...

Long shot but worth checking the crankshaft pulley. Mine worked loose (on a 200TDi) and buggered the injector timing.
From your description though it looks more like oil smoke, from valve seals or a piston ring (the latter might give you a tapping noise, as well as a bill for a new or recon block). are you sure it smells of diesel not oil?