Hey which Mercedes Diesel engines are compatible with the Discovery I auto gearbox?130CC said:If you plan on running SVO (straight vege oil) then there are modifications that are need to be made to the fuel system. Yes it must be preheated and the engine warm before switching from fosil (used at start up and shutdown of the engine) to SVO. after you have driven for a while switch to svo then drive a bit further 5 minutes before you turn off your car switch back to fossil. As SVO with become thicker as it cools something you don't want happening in the engine. From all I have read people only tend to run this system in older diesel engines(heaps of info can be found about the old Mec engine running to fuel delivery systems.)