Adjustment of diesel injection pump on 2.5 TD

Hi, Can anyone help with how to adjust the amount of fuel going through pump. I have tried turning it to and from engine but either it wont run properly or it is to advanced.
I just seem to have large amounts of black smoke on acceleration , on normal run it clears, but when it is ticking over it starts puffing out the back again so much so i feel sorry for anyone in a car or walking by, and you can even smell it in landy.
Any help more than welcome.
Cheers
Peters877

black smoke means its overfuelling

Rocking the pump back and forth on the timing case does not adjust the amount of fuel flowing through the pump. What you have adjusted is in fact the injection timing. If you feel down the side of the pump (on the engine side), there will be a long bolt sticking out of the housing towards the engine. All you need to do is wind this bolt in or out half a turn a time (I cant remember which way is to increase / restrict fuel flow) until the smoke stops. You can do it whilst the engine is running, so just have someone watching the exhaust as you adjust it. Once the black smoke stops, leave it be. You might benefit from then adjusting the timing of the fuel pump by rocking the pump, to or away from your engine so that it's spot on.