This might help you.
White smoke is normally ‘steam’ which means water is vapourising! If it is white ‘smoke’ then it could be as a result of low engine temperature. White Smoke will smell of unburned diesel - White ‘Steam’ will not!.
AFAIK, puwede lagyan yung old school diesel ng 2T sa fuel tank para makatulong sa decarbonizing. 128:1 ang ratio para safe. Done it already. No problems so far. Still checking the FC if it will improve but i doubt it. Decarbonize lang talaga.
http://www.dieselsmoke.com.au/